diff --git a/moto/elbv2/models.py b/moto/elbv2/models.py
index 4b3cf67ea..a748103e9 100644
--- a/moto/elbv2/models.py
+++ b/moto/elbv2/models.py
@@ -576,6 +576,9 @@ class FakeLoadBalancer(CloudFormationModel):
         "access_logs.s3.enabled",
         "access_logs.s3.bucket",
         "access_logs.s3.prefix",
+        "connection_logs.s3.bucket",
+        "connection_logs.s3.enabled",
+        "connection_logs.s3.prefix",
         "deletion_protection.enabled",
         "idle_timeout.timeout_seconds",
         "ipv6.deny_all_igw_traffic",
diff --git a/moto/elbv2/responses.py b/moto/elbv2/responses.py
index 2df73d292..8b50ab7bb 100644
--- a/moto/elbv2/responses.py
+++ b/moto/elbv2/responses.py
@@ -1578,40 +1578,6 @@ DESCRIBE_ATTRIBUTES_TEMPLATE = """<DescribeLoadBalancerAttributesResponse  xmlns
 </DescribeLoadBalancerAttributesResponse>
 """
 
-MODIFY_ATTRIBUTES_TEMPLATE = """<ModifyLoadBalancerAttributesResponse xmlns="http://elasticloadbalancing.amazonaws.com/doc/2015-12-01/">
-  <ModifyLoadBalancerAttributesResult>
-  <LoadBalancerName>{{ load_balancer.name }}</LoadBalancerName>
-    <LoadBalancerAttributes>
-      <AccessLog>
-        <Enabled>{{ attributes.access_log.enabled }}</Enabled>
-        {% if attributes.access_log.enabled %}
-        <S3BucketName>{{ attributes.access_log.s3_bucket_name }}</S3BucketName>
-        <S3BucketPrefix>{{ attributes.access_log.s3_bucket_prefix }}</S3BucketPrefix>
-        <EmitInterval>{{ attributes.access_log.emit_interval }}</EmitInterval>
-        {% endif %}
-      </AccessLog>
-      <ConnectionSettings>
-        <IdleTimeout>{{ attributes.connecting_settings.idle_timeout }}</IdleTimeout>
-      </ConnectionSettings>
-      <CrossZoneLoadBalancing>
-        <Enabled>{{ attributes.cross_zone_load_balancing.enabled }}</Enabled>
-      </CrossZoneLoadBalancing>
-      <ConnectionDraining>
-        {% if attributes.connection_draining.enabled %}
-        <Enabled>true</Enabled>
-        <Timeout>{{ attributes.connection_draining.timeout }}</Timeout>
-        {% else %}
-        <Enabled>false</Enabled>
-        {% endif %}
-      </ConnectionDraining>
-    </LoadBalancerAttributes>
-  </ModifyLoadBalancerAttributesResult>
-  <ResponseMetadata>
-    <RequestId>{{ request_id }}</RequestId>
-  </ResponseMetadata>
-</ModifyLoadBalancerAttributesResponse>
-"""
-
 CREATE_LOAD_BALANCER_POLICY_TEMPLATE = """<CreateLoadBalancerPolicyResponse xmlns="http://elasticloadbalancing.amazonaws.com/doc/2015-12-01/">
   <CreateLoadBalancerPolicyResult/>
   <ResponseMetadata>
diff --git a/tests/test_elbv2/test_elbv2.py b/tests/test_elbv2/test_elbv2.py
index cd933cb5a..4da6b059c 100644
--- a/tests/test_elbv2/test_elbv2.py
+++ b/tests/test_elbv2/test_elbv2.py
@@ -1291,6 +1291,28 @@ def test_modify_load_balancer_attributes_routing_http_drop_invalid_header_fields
     assert routing_http_drop_invalid_header_fields_enabled["Value"] == "false"
 
 
+@mock_elbv2
+@mock_ec2
+def test_modify_load_balancer_attributes_connection_logs_s3():
+    response, _, _, _, _, client = create_load_balancer()
+    arn = response["LoadBalancers"][0]["LoadBalancerArn"]
+
+    client.modify_load_balancer_attributes(
+        LoadBalancerArn=arn,
+        Attributes=[
+            {"Key": "connection_logs.s3.enabled", "Value": "true"},
+            {"Key": "connection_logs.s3.bucket", "Value": "s3bucket"},
+            {"Key": "connection_logs.s3.prefix", "Value": "test_prefix"},
+        ],
+    )
+
+    response = client.describe_load_balancer_attributes(LoadBalancerArn=arn)
+    attrs = client.describe_load_balancer_attributes(LoadBalancerArn=arn)["Attributes"]
+    assert {"Key": "connection_logs.s3.enabled", "Value": "true"} in attrs
+    assert {"Key": "connection_logs.s3.bucket", "Value": "s3bucket"} in attrs
+    assert {"Key": "connection_logs.s3.prefix", "Value": "test_prefix"} in attrs
+
+
 @mock_elbv2
 @mock_ec2
 @mock_acm