diff --git a/src/rez/tests/test_utils_py23.py b/src/rez/tests/test_utils_py23.py
new file mode 100644
index 000000000..96b2c04de
--- /dev/null
+++ b/src/rez/tests/test_utils_py23.py
@@ -0,0 +1,34 @@
+# SPDX-License-Identifier: Apache-2.0
+# Copyright Contributors to the Rez Project
+
+
+"""
+unit tests for 'utils.py23' module
+"""
+import os
+import sys
+import tempfile
+
+from rez.tests.util import TestBase
+from rez.utils import py23
+
+
+class TestLoadModuleFromFile(TestBase):
+    def test_load_module(self):
+        """Ensure that the imported module does not show up in sys.modules"""
+        # Random chars are used in the module name to ensure that the module name is unique
+        # and the test won't fail because some other module with the same name
+        # shows up in sys.modules
+        module = 'utils_test_7cd3a335'
+
+        filename = '{0}.py'.format(module)
+        tmpdir = tempfile.mkdtemp(prefix="rez_selftest_")
+
+        with open(os.path.join(tmpdir, filename), 'w') as fd:
+            fd.write('')
+
+        py23.load_module_from_file(
+            module,
+            os.path.join(tmpdir, filename)
+        )
+        self.assertEqual(sys.modules.get(module), None, msg='Module was found in sys.modules')
diff --git a/src/rez/utils/py23.py b/src/rez/utils/py23.py
index 3acb29271..09168a8e1 100644
--- a/src/rez/utils/py23.py
+++ b/src/rez/utils/py23.py
@@ -8,6 +8,8 @@
 Put any code here that deals with py2/3 interoperability, beyond simple cases
 that use (for eg) the six module.
 """
+import sys
+
 from rez.vendor.six import six
 
 
@@ -38,8 +40,20 @@ def load_module_from_file(name, filepath):
     if six.PY2:
         import imp
         with open(filepath) as f:
-            return imp.load_source(name, filepath, f)
+            module = imp.load_source(name, filepath, f)
+            # Keep the module out of sys.modules. See comment in the `else:`
+            # for more info
+            if name in sys.modules:
+                del sys.modules[name]
+            return module
 
     else:
-        from importlib.machinery import SourceFileLoader
-        return SourceFileLoader(name, filepath).load_module()
+        # The below code will import the module _without_ adding it to
+        # sys.modules. We want this otherwise we can't import multiple
+        # versions of the same module
+        # See: https://github.com/AcademySoftwareFoundation/rez/issues/1483
+        import importlib.util
+        spec = importlib.util.spec_from_file_location(name, filepath)
+        module = importlib.util.module_from_spec(spec)
+        spec.loader.exec_module(module)
+        return module