diff --git a/src/taskgraph/run-task/run-task b/src/taskgraph/run-task/run-task
index 905ca8175..8197b79aa 100755
--- a/src/taskgraph/run-task/run-task
+++ b/src/taskgraph/run-task/run-task
@@ -1010,7 +1010,8 @@ def install_pip_requirements(repositories):
     if not requirements:
         return
 
-    cmd = [sys.executable, "-mpip", "install"]
+    # TODO: Stop using system Python (#381)
+    cmd = [sys.executable, "-mpip", "install", "--break-system-packages"]
     if os.environ.get("PIP_DISABLE_REQUIRE_HASHES") != "1":
         cmd.append("--require-hashes")
 
diff --git a/test/test_scripts_run_task.py b/test/test_scripts_run_task.py
index 99da8ffa5..f0ed878c1 100644
--- a/test/test_scripts_run_task.py
+++ b/test/test_scripts_run_task.py
@@ -82,6 +82,7 @@ def test_install_pip_requirements(
             sys.executable,
             "-mpip",
             "install",
+            "--break-system-packages",
             "--require-hashes",
             "-r",
             str(req),
@@ -101,6 +102,7 @@ def test_install_pip_requirements(
             sys.executable,
             "-mpip",
             "install",
+            "--break-system-packages",
             "--require-hashes",
             "-r",
             str(req),