diff --git a/lib/fluent/plugin/out_http.rb b/lib/fluent/plugin/out_http.rb
index db6ba8158d..ec295db7b5 100644
--- a/lib/fluent/plugin/out_http.rb
+++ b/lib/fluent/plugin/out_http.rb
@@ -263,7 +263,6 @@ def set_headers(req, uri, chunk)
         end
       end
       req['Content-Type'] = @content_type
-      req['Host'] = uri.host
     end
 
     def set_auth(req, uri)
diff --git a/test/plugin/test_out_http.rb b/test/plugin/test_out_http.rb
index efb118d55e..04c80137b3 100644
--- a/test/plugin/test_out_http.rb
+++ b/test/plugin/test_out_http.rb
@@ -432,7 +432,6 @@ def test_aws_sigv4_sts_role_arn
       assert_equal 'application/x-ndjson', result.content_type
       assert_equal test_events, result.data
       assert_not_empty result.headers
-      assert_equal '127.0.0.1', result.headers['host']
       assert_not_nil result.headers['authorization']
       assert_match /AWS4-HMAC-SHA256 Credential=[a-zA-Z0-9]*\/\d+\/my-region-1\/someservice\/aws4_request/, result.headers['authorization']
       assert_match /SignedHeaders=content-type;host;x-amz-content-sha256;x-amz-date;x-amz-security-token/, result.headers['authorization']
@@ -470,7 +469,6 @@ def test_aws_sigv4_no_role
       assert_equal 'application/x-ndjson', result.content_type
       assert_equal test_events, result.data
       assert_not_empty result.headers
-      assert_equal '127.0.0.1', result.headers['host']
       assert_not_nil result.headers['authorization']
       assert_match /AWS4-HMAC-SHA256 Credential=[a-zA-Z0-9]*\/\d+\/my-region-1\/someservice\/aws4_request/, result.headers['authorization']
       assert_match /SignedHeaders=content-type;host;x-amz-content-sha256;x-amz-date;x-amz-security-token/, result.headers['authorization']