diff --git a/tests/structures/graphs/conftest.py b/tests/structures/graphs/conftest.py
index b7ea29c..abcb557 100644
--- a/tests/structures/graphs/conftest.py
+++ b/tests/structures/graphs/conftest.py
@@ -1,5 +1,5 @@
 from math import ceil, sqrt
-from random import choices, randint
+from random import choices, randint, seed
 from typing import Any, Dict, List, Set, Tuple, Type, Union
 
 import pytest
@@ -12,6 +12,11 @@
 MAX_WEIGHT = 1000
 
 
+def pytest_sessionstart(session):
+    """Initialize a fixed global random seed for the test session."""
+    seed(17)
+
+
 @pytest.fixture(
     scope="module",
     params=[