diff --git a/CHANGELOG.md b/CHANGELOG.md
index b8fb2bd3f4..ea5f2483ef 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -17,6 +17,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   ([#4270](https://github.com/open-telemetry/opentelemetry-python/pull/4270))
 - api: fix logging of duplicate EventLogger setup warning
   ([#4299](https://github.com/open-telemetry/opentelemetry-python/pull/4299))
+- sdk: fix serialization of logs severity_number field to int
+  ([#4324](https://github.com/open-telemetry/opentelemetry-python/pull/4324))
 
 ## Version 1.28.0/0.49b0 (2024-11-05)
 
diff --git a/opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py b/opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py
index 110bb89c99..c2db81687a 100644
--- a/opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py
+++ b/opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py
@@ -221,7 +221,9 @@ def to_json(self, indent=4) -> str:
         return json.dumps(
             {
                 "body": self.body,
-                "severity_number": repr(self.severity_number),
+                "severity_number": self.severity_number.value
+                if self.severity_number is not None
+                else None,
                 "severity_text": self.severity_text,
                 "attributes": (
                     dict(self.attributes) if bool(self.attributes) else None
diff --git a/opentelemetry-sdk/tests/logs/test_log_record.py b/opentelemetry-sdk/tests/logs/test_log_record.py
index 9c3746989b..f42d3a26ea 100644
--- a/opentelemetry-sdk/tests/logs/test_log_record.py
+++ b/opentelemetry-sdk/tests/logs/test_log_record.py
@@ -16,6 +16,7 @@
 import unittest
 import warnings
 
+from opentelemetry._logs.severity import SeverityNumber
 from opentelemetry.attributes import BoundedAttributes
 from opentelemetry.sdk._logs import (
     LogDroppedAttributesWarning,
@@ -30,7 +31,7 @@ def test_log_record_to_json(self):
         expected = json.dumps(
             {
                 "body": "a log line",
-                "severity_number": "None",
+                "severity_number": None,
                 "severity_text": None,
                 "attributes": None,
                 "dropped_attributes": 0,
@@ -56,9 +57,21 @@ def test_log_record_to_json(self):
         self.assertEqual(expected, actual.to_json(indent=4))
         self.assertEqual(
             actual.to_json(indent=None),
-            '{"body": "a log line", "severity_number": "None", "severity_text": null, "attributes": null, "dropped_attributes": 0, "timestamp": "1970-01-01T00:00:00.000000Z", "observed_timestamp": "1970-01-01T00:00:00.000000Z", "trace_id": "", "span_id": "", "trace_flags": null, "resource": {"attributes": {"service.name": "foo"}, "schema_url": ""}}',
+            '{"body": "a log line", "severity_number": null, "severity_text": null, "attributes": null, "dropped_attributes": 0, "timestamp": "1970-01-01T00:00:00.000000Z", "observed_timestamp": "1970-01-01T00:00:00.000000Z", "trace_id": "", "span_id": "", "trace_flags": null, "resource": {"attributes": {"service.name": "foo"}, "schema_url": ""}}',
         )
 
+    def test_log_record_to_json_serializes_severity_number_as_int(self):
+        actual = LogRecord(
+            timestamp=0,
+            severity_number=SeverityNumber.WARN,
+            observed_timestamp=0,
+            body="a log line",
+            resource=Resource({"service.name": "foo"}),
+        )
+
+        decoded = json.loads(actual.to_json())
+        self.assertEqual(SeverityNumber.WARN.value, decoded["severity_number"])
+
     def test_log_record_bounded_attributes(self):
         attr = {"key": "value"}