A mechanism for locking the fins of a missile in place when the missile is not in use utilizes tabs inserted in slots of the output shafts of the fins to immobilize the output shafts and the fins. In one embodiment, the tabs are cantilevered on a locking plate from which they extend radially toward the output shafts. A cam plate slidably engages the tabs on the locking plate and simultaneously lifts all the tabs out of the slots when it is rotated. for disengagement of the locking mechanism. Operation of the locking mechanism can be effected either manually, using a specialized tool, or remotely, using for example a pyrotechnic actuation device.