The invention provides a multifunctional clamping device for mechanical teaching. The multifunctional clamping device comprises a base, a blind hole, a spring, a V-shaped groove, a conical head, a clamping screw rod, a rotating disc, a connecting shaft, a flange plate, a positioning cone and a rotating table. By means of the multifunctional clamping device, various clamping mechanisms are provided, in addition, the base and the rotating table are made of transparent materials, and therefore students can better watch the working movement process during demonstration, and the study interesting of the students is greatly improved. The conical head moves rightwards to make contact with the V-shaped groove so that the connecting shaft can be used for driving the rotating table to move downwardsto be locked on the base, and it is ensured that the rotating table cannot rotate. In addition, a left rotation screw and a right rotation screw rod can also be rotated to drive a clamping plate anda clamping seat to inwards clamp a clamping sleeve on the outer side of the rotating table at the same time, and therefore it can also be ensured that the rotating table cannot rotate. By means of thetwo kinds of clamping structures, the students can be greatly enlightened to thick how to make the rotating table not rotate when other structures exist or do not exist.