The invention discloses a universal fixture of a roughly turned sliding fork excircle, which comprises a transition plate, wherein a through sliding groove of which the cross section is T-shaped is formed on one side face of the transition plate along the equally dividing central line; two T-shaped slide blocks which are symmetrical around the centre of the transition plate are arranged in the sliding groove; each slide block is connected with a detachable V-shaped block through an axial fastening screw; a limit strip extending into the sliding groove is arranged on one side, close to the transition plate, of the V-shaped block; and a positioning mechanism is axially arranged in the centre of the transition plate. The universer fixture has the advantages that: the design is reasonable, the structure is simple, the shortcomings of a traditional fixture are overcome, the requirements of excircle processing of various sliding forks are met, the processing precision of parts is improved, convenience in quick adjustment is realized, the relative distance of the V-shaped blocks can be adjusted only by loosening screws, the aim of replacing processes varieties can be fulfilled by replacing a positioning shaft and a centring plate, the number of fixtures is correspondingly reduced, the manufacturing cost and inventory of the fixtures are saved, the production efficiency is improved, and the effect is obvious.