diff --git a/scrapy/conf/__init__.py b/scrapy/conf/__init__.py
index 4b4d6d58caff0cc39258bf31928aa6bd8109b3b4..d7c20d68e932e85898a60840c5129ac939e139ca 100644
--- a/scrapy/conf/__init__.py
+++ b/scrapy/conf/__init__.py
@@ -14,10 +14,12 @@ class Settings(object):
     default_settings_module = 'scrapy.conf.default_settings'
 
     def __init__(self):
-        self.set_settings_module()
         self.defaults = {}
         self.global_defaults = import_(self.default_settings_module)
         self.disabled = os.environ.get('SCRAPY_SETTINGS_DISABLED', False)
+        settings_module_path = os.environ.get('SCRAPYSETTINGS_MODULE', \
+            'scrapy_settings')
+        self.set_settings_module(settings_module_path)
 
         # XXX: find a better solution for this hack
         pickled_settings = os.environ.get("SCRAPY_PICKLED_SETTINGS_TO_OVERRIDE")
@@ -35,10 +37,7 @@ class Settings(object):
                 return self.defaults[opt_name]
         return getattr(self.global_defaults, opt_name, None)
 
-    def set_settings_module(self, settings_module_path=None):
-        if settings_module_path is None:
-            settings_module_path = os.environ.get('SCRAPYSETTINGS_MODULE', \
-                'scrapy_settings')
+    def set_settings_module(self, settings_module_path):
         self.settings_module_path = settings_module_path
         try:
             self.settings_module = import_(settings_module_path)