A rotation module includes a base and a rotation member rotatably positioned on the base. The base includes a resisting surface and a connecting surface opposite to the resisting surface. A cylindrical protrusion is formed on the resisting surface. A locking portion is formed at an end of the cylindrical protrusion. The cylindrical protrusion defines an opening through the locking portion. The rotation member includes a bottom surface and a supporting surface opposite to the bottom surface. The rotation member defines a circular through hole. The locking portion is deformable due to the opening so that the cylindrical protrusion is able to pass through the circular through hole. The locking portion releases after the locking portion passes through the circular through hole and resists the rotation member to prevent the rotation member from detaching from the base.