A driving mechanism is provided, including a case, a holder and a driving module. The holder is disposed in the case for holding an optical member. The driving module is disposed in the case for driving the holder. The case is substantially quadrilateral and includes a first side and a second side. The driving module includes a first magnetic driving component winding on a periphery of the holder. The first magnetic driving component includes a first segment and a second segment that are respectively substantially parallel to the first side and the second side. The distance between the first segment and the first side is different from the distance between the second segment and the second side.