A crutch includes a main frame mainly constructed of two spaced posts, wherein each post defines multiple positioning holes. A handgrip includes a main piece and two fasteners. The main piece defines two receiving spaces at its two ends for receiving the posts of the main frame. Each fastener has a positioning stud, a first portion, and a second portion. The first and second portions enclose one post of the main frame and can be operated to move between a first position and a second position. When each fastener is moved to the first position, the positioning stud is inserted into one of the positioning holes, while the first portion is engaged with the main piece. When the fastener is moved to the second position, the positioning stud is clear of the positioning hole, while the fastener is unable to leave the post.