diff --git a/app/server/models.py b/app/server/models.py
index 004adc23..6eec7fb7 100644
--- a/app/server/models.py
+++ b/app/server/models.py
@@ -184,6 +184,38 @@ class Document(models.Model):
                    for a in annotations]
         return dataset
 
+    def to_json(self):
+        return self.make_dataset_json()
+
+    def make_dataset_json(self):
+        if self.project.is_type_of(Project.DOCUMENT_CLASSIFICATION):
+            return self.make_dataset_for_classification_json()
+        elif self.project.is_type_of(Project.SEQUENCE_LABELING):
+            return self.make_dataset_for_sequence_labeling_json()
+        elif self.project.is_type_of(Project.Seq2seq):
+            return self.make_dataset_for_seq2seq_json()
+
+    def make_dataset_for_classification_json(self):
+        annotations = self.get_annotations()
+        labels = [a.label.text for a in annotations]
+        username = annotations[0].user.username
+        dataset = {'doc_id': self.id, 'text': self.text, 'labels': labels, 'username': username}
+        return dataset
+
+    def make_dataset_for_sequence_labeling_json(self):
+        annotations = self.get_annotations()
+        entities = [(a.start_offset, a.end_offset, a.label.text) for a in annotations]
+        username = annotations[0].user.username
+        dataset = {'doc_id': self.id, 'text': self.text, 'entities': entities, 'username': username}
+        return dataset
+
+    def make_dataset_for_seq2seq_json(self):
+        annotations = self.get_annotations()
+        sentences = [a.text for a in annotations]
+        username = annotations[0].user.username
+        dataset = {'doc_id': self.id, 'text': self.text, 'sentences': sentences, 'username': username}
+        return dataset
+
     def __str__(self):
         return self.text[:50]
 
diff --git a/app/server/views.py b/app/server/views.py
index 4b266eea..1ecd4c59 100644
--- a/app/server/views.py
+++ b/app/server/views.py
@@ -104,7 +104,7 @@ class DataDownloadFile(SuperUserMixin, LoginRequiredMixin, View):
                 response = self.get_json(filename, docs)
             return response
         except:
-            return HttpResponseRedirect(reverse('download', args=[project.id]))
+            return HttpResponseRedirect(reverse('upload', args=[project.id]))
 
     def get_csv(self, filename, docs):
         response = HttpResponse(content_type='text/csv')
@@ -115,7 +115,13 @@ class DataDownloadFile(SuperUserMixin, LoginRequiredMixin, View):
         return response
 
     def get_json(self, filename, docs):
-        pass
+        response = HttpResponse(content_type='text/json')
+        response['Content-Disposition'] = 'attachment; filename="{}.json"'.format(filename)
+        for d in docs:
+            dump = json.dumps(d.to_json(), ensure_ascii=False)
+            response.write(dump + '\n') # write each json object end with a newline
+        print('dump done')
+        return response
 
 
 class DemoTextClassification(TemplateView):