diff --git a/pisi/api.py b/pisi/api.py
index 7f4157da..13da3d56 100644
--- a/pisi/api.py
+++ b/pisi/api.py
@@ -583,6 +583,9 @@ def add_repo(name, indexuri, at = None):
     repodb = pisi.db.repodb.RepoDB()
     if repodb.has_repo(name):
         raise pisi.Error(_('Repo %s already present.') % name)
+    elif repodb.has_repo_url(indexuri):
+        repo = repodb.get_repo_by_url(indexuri)
+        raise pisi.Error(_('Repo already present with name %s.') % repo)
     else:
         repo = pisi.db.repodb.Repo(pisi.uri.URI(indexuri))
         repodb.add_repo(name, repo, at = at)
diff --git a/pisi/db/repodb.py b/pisi/db/repodb.py
index f41f8284..7655dc23 100644
--- a/pisi/db/repodb.py
+++ b/pisi/db/repodb.py
@@ -166,3 +166,11 @@ class RepoDB(lazydb.LazyDB):
         for r in self.list_repos():
             repos.append(self.get_repo_url(r))
         return repos
+
+    def get_repo_by_url(self, url):
+        if not self.has_repo_url(url):
+            return None
+
+        for r in self.list_repos():
+            if self.get_repo_url(r) == url:
+                return r