diff --git a/pyqtgraph/__init__.py b/pyqtgraph/__init__.py
index 12a4f90f..f6eafb60 100644
--- a/pyqtgraph/__init__.py
+++ b/pyqtgraph/__init__.py
@@ -139,7 +139,7 @@ def importModules(path, globals, locals, excludes=()):
     d = os.path.join(os.path.split(globals['__file__'])[0], path)
     files = set()
     for f in frozenSupport.listdir(d):
-        if frozenSupport.isdir(os.path.join(d, f)) and f != '__pycache__':
+        if frozenSupport.isdir(os.path.join(d, f)) and f not in ['__pycache__', 'tests']:
             files.add(f)
         elif f[-3:] == '.py' and f != '__init__.py':
             files.add(f[:-3])