diff --git a/iotdb-client/client-py/iotdb/utils/rpc_utils.py b/iotdb-client/client-py/iotdb/utils/rpc_utils.py
index 0912fd14d95de..601cd99cf7406 100644
--- a/iotdb-client/client-py/iotdb/utils/rpc_utils.py
+++ b/iotdb-client/client-py/iotdb/utils/rpc_utils.py
@@ -17,6 +17,7 @@
 #
 import logging
 
+import numpy as np
 import pandas as pd
 from pandas._libs import OutOfBoundsDatetime
 from tzlocal import get_localzone_name
@@ -81,10 +82,12 @@ def convert_to_timestamp(time: int, precision: str, timezone: str):
     try:
         ts = pd.Timestamp(time, unit=precision, tz=timezone)
     except OutOfBoundsDatetime:
+        # Preserve the input unit: pandas 3.1 may overflow when constructing
+        # extreme millisecond timestamps directly from an integer.
         try:
-            ts = pd.Timestamp(time, unit=precision).tz_localize(timezone)
+            ts = pd.Timestamp(np.datetime64(int(time), precision)).tz_localize(timezone)
         except NotImplementedError:
-            return pd.Timestamp(time, unit=precision)
+            return pd.Timestamp(np.datetime64(int(time), precision))
     except ValueError:
         logger.warning(
             f"Timezone string '{timezone}' cannot be recognized by pandas. "
@@ -95,7 +98,7 @@ def convert_to_timestamp(time: int, precision: str, timezone: str):
         # Timestamp falls outside Python's stdlib datetime range (year < 1 or
         # > 9999). pandas >= 3.0 cannot attach a timezone to such Timestamps
         # because tz conversion relies on toordinal(). Return naive instead.
-        return pd.Timestamp(time, unit=precision)
+        return pd.Timestamp(np.datetime64(int(time), precision))
     # Construction succeeded but utcoffset() may still fail downstream (e.g.
     # in pd.DataFrame's tz alignment) when the Timestamp's year is outside
     # 1..9999 and tz is not the canonical UTC. Probe early and fall back to
@@ -105,7 +108,7 @@ def convert_to_timestamp(time: int, precision: str, timezone: str):
         try:
             ts.utcoffset()
         except NotImplementedError:
-            return pd.Timestamp(time, unit=precision)
+            return pd.Timestamp(np.datetime64(int(time), precision))
     return ts
 
 
diff --git a/iotdb-client/client-py/tests/unit/test_rpc_utils.py b/iotdb-client/client-py/tests/unit/test_rpc_utils.py
new file mode 100644
index 0000000000000..c34e6e4a961de
--- /dev/null
+++ b/iotdb-client/client-py/tests/unit/test_rpc_utils.py
@@ -0,0 +1,56 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+
+from datetime import timedelta
+
+import numpy as np
+import pandas as pd
+import pytest
+
+from iotdb.utils.rpc_utils import convert_to_timestamp, isoformat
+
+
+@pytest.mark.parametrize("precision", ["ms", "us", "ns"])
+@pytest.mark.parametrize("value", [-(2**63) + 1, 2**63 - 1])
+def test_timestamp_boundaries_keep_value_and_precision(precision, value):
+    for scalar in (value, np.int64(value)):
+        for timezone in ("UTC", "Etc/UTC"):
+            timestamp = convert_to_timestamp(scalar, precision, timezone)
+            assert timestamp.asm8.dtype == np.dtype(f"datetime64[{precision}]")
+            assert timestamp.asm8.astype(np.int64) == value
+            if timestamp.tzinfo is not None:
+                assert timestamp.utcoffset() == timedelta(0)
+            expected = np.datetime_as_string(np.datetime64(value, precision))
+            formatted = isoformat(timestamp, precision)
+            if formatted.endswith("+00:00"):
+                formatted = formatted[:-6]
+            assert formatted == expected
+
+
+@pytest.mark.parametrize("precision", ["ms", "us", "ns"])
+@pytest.mark.parametrize("timezone", ["UTC", "Asia/Shanghai"])
+def test_normal_timestamp_keeps_timezone(precision, timezone):
+    value = 123456789
+    timestamp = convert_to_timestamp(value, precision, timezone)
+    assert timestamp == pd.Timestamp(value, unit=precision, tz=timezone)
+    assert str(timestamp.tzinfo) == timezone
+
+
+def test_timestamp_nat_is_preserved():
+    for precision in ("ms", "us", "ns"):
+        assert convert_to_timestamp(-(2**63), precision, "Etc/UTC") is pd.NaT