diff --git a/haystack/nodes/extractor/entity.py b/haystack/nodes/extractor/entity.py
index 4c864de75..9b16528c5 100644
--- a/haystack/nodes/extractor/entity.py
+++ b/haystack/nodes/extractor/entity.py
@@ -317,7 +317,7 @@ class EntityExtractor(BaseComponent):
         offset_mapping = model_inputs.pop("offset_mapping", None)
         overflow_to_sample_mapping = model_inputs.pop("overflow_to_sample_mapping")
 
-        logits = self.model(**model_inputs)[0]
+        logits = self.model(**model_inputs)[0].to(torch.float64)
 
         return {
             "logits": logits,
@@ -766,8 +766,8 @@ class _EntityPostProcessor:
             "score": score,
             "word": word,
             "tokens": tokens,
-            "start": entities[0]["start"],
-            "end": entities[-1]["end"],
+            "start": int(entities[0]["start"]),
+            "end": int(entities[-1]["end"]),
         }
         return new_entity
 
diff --git a/releasenotes/notes/fix-entityextractor-json-serialzable-b7d643eb83a3e58c.yaml b/releasenotes/notes/fix-entityextractor-json-serialzable-b7d643eb83a3e58c.yaml
new file mode 100644
index 000000000..ad1415b8f
--- /dev/null
+++ b/releasenotes/notes/fix-entityextractor-json-serialzable-b7d643eb83a3e58c.yaml
@@ -0,0 +1,4 @@
+---
+fixes:
+  - |
+    Fix EntityExtractor output not JSON serializable.