The invention discloses a mechanical molding drum and a tire bead slipping detection device and method. The tire bead slipping detection device comprises a locking block (3), a pressure sensor (2) andalarm equipment, wherein the pressure sensor (2) is arranged on the locking block (3) and used for detecting the contact pressure between the locking block (3) and a tire bead, the pressure sensor (2) is in communication connection with a driving device used for driving the locking block (3) to move, and the alarm equipment is in communication connection with the pressure sensor (2). According tothe tire bead slipping detection device, the situation of position slipping of the tire bead in the molding process of a green tire is avoided, the situation that semi-finished products which are severe in slippage flow into a next process is further avoided, the tire making stability is effectively improved, the probability of defective goods is decreased, and the production cost is reduced.