diff --git a/src/services/json-api-datastore.service.ts b/src/services/json-api-datastore.service.ts
index 3c0493c3..3f729eb0 100644
--- a/src/services/json-api-datastore.service.ts
+++ b/src/services/json-api-datastore.service.ts
@@ -246,6 +246,16 @@ export class JsonApiDatastore {
               data: relationshipData
             };
           }
+        }  else if (data[key] === null) {
+          const entity = belongsToMetadata.find((entity: any) => entity.propertyName === key);
+
+          if (entity) {
+            relationships = relationships || {};
+
+            relationships[entity.relationship] = {
+              data: null
+            };
+          }
         }
       }
     }
@@ -448,7 +458,7 @@ export class JsonApiDatastore {
     const modelsTypes: any = Reflect.getMetadata('JsonApiDatastoreConfig', this.constructor).models;
 
     for (const relationship in relationships) {
-      if (relationships.hasOwnProperty(relationship) && model.hasOwnProperty(relationship)) {
+      if (relationships.hasOwnProperty(relationship) && model.hasOwnProperty(relationship) && model[relationship]) {
         const relationshipModel: JsonApiModel = model[relationship];
         const hasMany: any[] = Reflect.getMetadata('HasMany', relationshipModel);
         const propertyHasMany: any = find(hasMany, (property) => {