An engagement structure for a cable head includes a main body and a release mechanism. The main body has movable positioners disposed thereon. When the cable head is inserted in the main body, the positioners are temporarily pushed away and moved back by an elastic mechanism to block the cable head from removing from the main body. For removing the cable head, a release mechanism is configured for pushing the positioners away. Thus, user can remove the cable head by operating the release mechanism. Therefore, operation of the engagement structure is simplified for user.