diff --git a/rest_framework_json_api/renderers.py b/rest_framework_json_api/renderers.py
index 60836e97..619e730d 100644
--- a/rest_framework_json_api/renderers.py
+++ b/rest_framework_json_api/renderers.py
@@ -86,6 +86,10 @@ def extract_relationships(cls, fields, resource, resource_instance):
             if field_name == api_settings.URL_FIELD_NAME:
                 continue
 
+            # don't output a key for write only fields
+            if fields[field_name].write_only:
+                continue
+
             # Skip fields without relations
             if not isinstance(
                 field, (relations.RelatedField, relations.ManyRelatedField, BaseSerializer)