Disclosed is a single wedge wrench including two jaws, one of which has a zigzag gripping surface. The wrench further includes a wedge having a zigzag gripping surface. The wedge is mounted on an inner surface of the other one of the two jaws by means of a joint member, being slidable along the inner surface. The wrench disclosed can be used for bolts or nuts with various types and sizes, and an operation can be performed as long as a handle of the wrench is returned. The wrench can be manufactured with a simple process in a production line.