diff --git a/IMPLEMENTATION_COVERAGE.md b/IMPLEMENTATION_COVERAGE.md
index 0f2e7c4ff..464893986 100644
--- a/IMPLEMENTATION_COVERAGE.md
+++ b/IMPLEMENTATION_COVERAGE.md
@@ -2481,6 +2481,70 @@
 - [ ] update_workflow
 </details>
 
+## guardduty
+<details>
+<summary>3% implemented</summary>
+
+- [ ] accept_invitation
+- [ ] archive_findings
+- [X] create_detector
+- [ ] create_filter
+- [ ] create_ip_set
+- [ ] create_members
+- [ ] create_publishing_destination
+- [ ] create_sample_findings
+- [ ] create_threat_intel_set
+- [ ] decline_invitations
+- [ ] delete_detector
+- [ ] delete_filter
+- [ ] delete_invitations
+- [ ] delete_ip_set
+- [ ] delete_members
+- [ ] delete_publishing_destination
+- [ ] delete_threat_intel_set
+- [ ] describe_organization_configuration
+- [ ] describe_publishing_destination
+- [ ] disable_organization_admin_account
+- [ ] disassociate_from_master_account
+- [ ] disassociate_members
+- [ ] enable_organization_admin_account
+- [ ] get_detector
+- [ ] get_filter
+- [ ] get_findings
+- [ ] get_findings_statistics
+- [ ] get_invitations_count
+- [ ] get_ip_set
+- [ ] get_master_account
+- [ ] get_member_detectors
+- [ ] get_members
+- [ ] get_threat_intel_set
+- [ ] get_usage_statistics
+- [ ] invite_members
+- [X] list_detectors
+- [ ] list_filters
+- [ ] list_findings
+- [ ] list_invitations
+- [ ] list_ip_sets
+- [ ] list_members
+- [ ] list_organization_admin_accounts
+- [ ] list_publishing_destinations
+- [ ] list_tags_for_resource
+- [ ] list_threat_intel_sets
+- [ ] start_monitoring_members
+- [ ] stop_monitoring_members
+- [ ] tag_resource
+- [ ] unarchive_findings
+- [ ] untag_resource
+- [ ] update_detector
+- [ ] update_filter
+- [ ] update_findings_feedback
+- [ ] update_ip_set
+- [ ] update_member_detectors
+- [ ] update_organization_configuration
+- [ ] update_publishing_destination
+- [ ] update_threat_intel_set
+</details>
+
 ## iam
 <details>
 <summary>67% implemented</summary>
@@ -4945,7 +5009,6 @@
 - greengrass
 - greengrassv2
 - groundstation
-- guardduty
 - health
 - healthlake
 - honeycode
diff --git a/docs/docs/services/guardduty.rst b/docs/docs/services/guardduty.rst
new file mode 100644
index 000000000..9189ce47a
--- /dev/null
+++ b/docs/docs/services/guardduty.rst
@@ -0,0 +1,90 @@
+.. _implementedservice_guardduty:
+
+.. |start-h3| raw:: html
+
+    <h3>
+
+.. |end-h3| raw:: html
+
+    </h3>
+
+=========
+guardduty
+=========
+
+|start-h3| Example usage |end-h3|
+
+.. sourcecode:: python
+
+            @mock_guardduty
+            def test_guardduty_behaviour:
+                boto3.client("guardduty")
+                ...
+
+
+
+|start-h3| Implemented features for this service |end-h3|
+
+- [ ] accept_invitation
+- [ ] archive_findings
+- [X] create_detector
+- [ ] create_filter
+- [ ] create_ip_set
+- [ ] create_members
+- [ ] create_publishing_destination
+- [ ] create_sample_findings
+- [ ] create_threat_intel_set
+- [ ] decline_invitations
+- [ ] delete_detector
+- [ ] delete_filter
+- [ ] delete_invitations
+- [ ] delete_ip_set
+- [ ] delete_members
+- [ ] delete_publishing_destination
+- [ ] delete_threat_intel_set
+- [ ] describe_organization_configuration
+- [ ] describe_publishing_destination
+- [ ] disable_organization_admin_account
+- [ ] disassociate_from_master_account
+- [ ] disassociate_members
+- [ ] enable_organization_admin_account
+- [ ] get_detector
+- [ ] get_filter
+- [ ] get_findings
+- [ ] get_findings_statistics
+- [ ] get_invitations_count
+- [ ] get_ip_set
+- [ ] get_master_account
+- [ ] get_member_detectors
+- [ ] get_members
+- [ ] get_threat_intel_set
+- [ ] get_usage_statistics
+- [ ] invite_members
+- [X] list_detectors
+  
+        The MaxResults and NextToken-parameter have not yet been implemented.
+        
+
+- [ ] list_filters
+- [ ] list_findings
+- [ ] list_invitations
+- [ ] list_ip_sets
+- [ ] list_members
+- [ ] list_organization_admin_accounts
+- [ ] list_publishing_destinations
+- [ ] list_tags_for_resource
+- [ ] list_threat_intel_sets
+- [ ] start_monitoring_members
+- [ ] stop_monitoring_members
+- [ ] tag_resource
+- [ ] unarchive_findings
+- [ ] untag_resource
+- [ ] update_detector
+- [ ] update_filter
+- [ ] update_findings_feedback
+- [ ] update_ip_set
+- [ ] update_member_detectors
+- [ ] update_organization_configuration
+- [ ] update_publishing_destination
+- [ ] update_threat_intel_set
+
diff --git a/moto/__init__.py b/moto/__init__.py
index b5879e4c0..f7191f1ea 100644
--- a/moto/__init__.py
+++ b/moto/__init__.py
@@ -95,6 +95,7 @@ mock_forecast = lazy_load(".forecast", "mock_forecast")
 mock_glacier = lazy_load(".glacier", "mock_glacier")
 mock_glacier_deprecated = lazy_load(".glacier", "mock_glacier_deprecated")
 mock_glue = lazy_load(".glue", "mock_glue")
+mock_guardduty = lazy_load(".guardduty", "mock_guardduty")
 mock_iam = lazy_load(".iam", "mock_iam")
 mock_iam_deprecated = lazy_load(".iam", "mock_iam_deprecated")
 mock_iot = lazy_load(".iot", "mock_iot")
@@ -198,7 +199,6 @@ class MockAll(ContextDecorator):
 
 mock_all = MockAll
 
-
 # import logging
 # logging.getLogger('boto').setLevel(logging.CRITICAL)
 
diff --git a/moto/backend_index.py b/moto/backend_index.py
index b85b7e3a2..3fed47bfb 100644
--- a/moto/backend_index.py
+++ b/moto/backend_index.py
@@ -66,6 +66,7 @@ backend_url_patterns = [
     ("forecast", re.compile("https?://forecast\\.(.+)\\.amazonaws\\.com")),
     ("glacier", re.compile("https?://glacier\\.(.+)\\.amazonaws.com")),
     ("glue", re.compile("https?://glue\\.(.+)\\.amazonaws\\.com")),
+    ("guardduty", re.compile("https?://guardduty\\.(.+)\\.amazonaws\\.com")),
     ("iam", re.compile("https?://iam\\.(.*\\.)?amazonaws\\.com")),
     ("iot", re.compile("https?://iot\\.(.+)\\.amazonaws\\.com")),
     ("iot-data", re.compile("https?://data\\.iot\\.(.+)\\.amazonaws.com")),
diff --git a/moto/guardduty/__init__.py b/moto/guardduty/__init__.py
new file mode 100644
index 000000000..68e09dedd
--- /dev/null
+++ b/moto/guardduty/__init__.py
@@ -0,0 +1,7 @@
+from __future__ import unicode_literals
+
+from .models import guardduty_backends
+from ..core.models import base_decorator
+
+guardduty_backend = guardduty_backends["us-east-1"]
+mock_guardduty = base_decorator(guardduty_backends)
diff --git a/moto/guardduty/models.py b/moto/guardduty/models.py
new file mode 100644
index 000000000..38518e313
--- /dev/null
+++ b/moto/guardduty/models.py
@@ -0,0 +1,79 @@
+from __future__ import unicode_literals
+from boto3 import Session
+from moto.core import BaseBackend, BaseModel
+from datetime import datetime
+from uuid import uuid4
+
+
+class GuardDutyBackend(BaseBackend):
+    def __init__(self, region_name=None):
+        super(GuardDutyBackend, self).__init__()
+        self.region_name = region_name
+        self.detectors = {}
+
+    def reset(self):
+        region_name = self.region_name
+        self.__dict__ = {}
+        self.__init__(region_name)
+
+    def create_detector(
+        self, enable, client_token, finding_publishing_frequency, data_sources, tags
+    ):
+        if finding_publishing_frequency not in [
+            "FIFTEEN_MINUTES",
+            "ONE_HOUR",
+            "SIX_HOURS",
+        ]:
+            finding_publishing_frequency = "SIX_HOURS"
+
+        service_role = "AWSServiceRoleForAmazonGuardDuty"
+        detector = Detector(
+            self,
+            datetime.now,
+            finding_publishing_frequency,
+            service_role,
+            enable,
+            data_sources,
+            tags,
+        )
+        self.detectors[detector.id] = detector
+        return detector.id
+
+    def list_detectors(self):
+        """
+        The MaxResults and NextToken-parameter have not yet been implemented.
+        """
+        detectorids = []
+        for detector in self.detectors:
+            detectorids.append(self.detectors[detector].id)
+        return detectorids
+
+
+class Detector(BaseModel):
+    def __init__(
+        self,
+        created_at,
+        finding_publish_freq,
+        service_role,
+        status,
+        updated_at,
+        datasources,
+        tags,
+    ):
+        self.id = str(uuid4())
+        self.created_at = created_at
+        self.finding_publish_freq = finding_publish_freq
+        self.service_role = service_role
+        self.status = status
+        self.updated_at = updated_at
+        self.datasources = datasources
+        self.tags = tags
+
+
+guardduty_backends = {}
+for region in Session().get_available_regions("guardduty"):
+    guardduty_backends[region] = GuardDutyBackend()
+for region in Session().get_available_regions("guardduty", partition_name="aws-us-gov"):
+    guardduty_backends[region] = GuardDutyBackend()
+for region in Session().get_available_regions("guardduty", partition_name="aws-cn"):
+    guardduty_backends[region] = GuardDutyBackend()
diff --git a/moto/guardduty/responses.py b/moto/guardduty/responses.py
new file mode 100644
index 000000000..77d55c384
--- /dev/null
+++ b/moto/guardduty/responses.py
@@ -0,0 +1,39 @@
+from __future__ import unicode_literals
+from moto.core.responses import BaseResponse
+from .models import guardduty_backends
+import json
+
+
+class GuardDutyResponse(BaseResponse):
+    SERVICE_NAME = "guardduty"
+
+    @property
+    def guardduty_backend(self):
+        return guardduty_backends[self.region]
+
+    def detector(self, request, full_url, headers):
+        self.setup_class(request, full_url, headers)
+        if request.method == "POST":
+            return self.create_detector()
+        elif request.method == "GET":
+            return self.list_detectors()
+        else:
+            return 404, {}, ""
+
+    def create_detector(self):
+        enable = self._get_param("enable")
+        client_token = self._get_param("clientToken")
+        finding_publishing_frequency = self._get_param("findingPublishingFrequency")
+        data_sources = self._get_param("dataSources")
+        tags = self._get_param("tags")
+
+        detector_id = self.guardduty_backend.create_detector(
+            enable, client_token, finding_publishing_frequency, data_sources, tags
+        )
+
+        return 200, {}, json.dumps(dict(detectorId=detector_id))
+
+    def list_detectors(self):
+        detector_ids = self.guardduty_backend.list_detectors()
+
+        return 200, {}, json.dumps({"detectorIds": detector_ids})
diff --git a/moto/guardduty/urls.py b/moto/guardduty/urls.py
new file mode 100644
index 000000000..6012d35c9
--- /dev/null
+++ b/moto/guardduty/urls.py
@@ -0,0 +1,13 @@
+from __future__ import unicode_literals
+from .responses import GuardDutyResponse
+
+response = GuardDutyResponse()
+
+url_bases = [
+    "https?://guardduty\\.(.+)\\.amazonaws\\.com",
+]
+
+
+url_paths = {
+    "{0}/detector$": response.detector,
+}
diff --git a/tests/test_guardduty/__init__.py b/tests/test_guardduty/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/tests/test_guardduty/test_guardduty.py b/tests/test_guardduty/test_guardduty.py
new file mode 100644
index 000000000..72ff4c9fb
--- /dev/null
+++ b/tests/test_guardduty/test_guardduty.py
@@ -0,0 +1,51 @@
+import boto3
+import sure  # noqa # pylint: disable=unused-import
+
+from moto import mock_guardduty
+
+
+@mock_guardduty
+def test_create_detector():
+    client = boto3.client("guardduty", region_name="us-east-1")
+    response = client.create_detector(
+        Enable=True,
+        ClientToken="745645734574758463758",
+        FindingPublishingFrequency="ONE_HOUR",
+        DataSources={"S3Logs": {"Enable": True}},
+        Tags={},
+    )
+    response.should.have.key("DetectorId")
+    response["DetectorId"].shouldnt.equal(None)
+
+
+@mock_guardduty
+def test_create_detector_with_minimal_params():
+    client = boto3.client("guardduty", region_name="us-east-1")
+    response = client.create_detector(Enable=True)
+    response.should.have.key("DetectorId")
+    response["DetectorId"].shouldnt.equal(None)
+
+
+@mock_guardduty
+def test_list_detectors_initial():
+    client = boto3.client("guardduty", region_name="us-east-1")
+
+    response = client.list_detectors()
+    response.should.have.key("DetectorIds").equals([])
+
+
+@mock_guardduty
+def test_list_detectors():
+    client = boto3.client("guardduty", region_name="us-east-1")
+    d1 = client.create_detector(
+        Enable=True,
+        ClientToken="745645734574758463758",
+        FindingPublishingFrequency="ONE_HOUR",
+        DataSources={"S3Logs": {"Enable": True}},
+        Tags={},
+    )["DetectorId"]
+    d2 = client.create_detector(Enable=False,)["DetectorId"]
+
+    response = client.list_detectors()
+    response.should.have.key("DetectorIds")
+    set(response["DetectorIds"]).should.equal({d1, d2})
diff --git a/tests/test_guardduty/test_server.py b/tests/test_guardduty/test_server.py
new file mode 100644
index 000000000..4a09532fa
--- /dev/null
+++ b/tests/test_guardduty/test_server.py
@@ -0,0 +1,14 @@
+import json
+import sure  # noqa # pylint: disable=unused-import
+
+import moto.server as server
+
+
+def test_create_without_enable_option():
+    backend = server.create_backend_app("guardduty")
+    test_client = backend.test_client()
+
+    body = {"enable": "True"}
+    response = test_client.post("/detector", data=json.dumps(body))
+    response.status_code.should.equal(200)
+    json.loads(response.data).should.have.key("detectorId")