A compound safety hinge for folding doors comprises a pair of elongated vertical stationary horizontally-slotted tubular connectors each having therein an elongated sleeve insert which is pivotal through an angle limited by the length of the slots, typically through 90*. One vertical edge of each door panel is fastened to one edge of an elongated casing. The other edge of each casing abuts against one of the stationary tubular connectors and is fastened to the pivotal insert by fastening pins or screws which extend through the slots in the stationary connector. Each stationary tubular connector is provided with an outward flange which mates with, and is connected to, the flange of the other stationary tubular connector. The lower end of the pivotal tubular insert is provided with an outward annular flange which serves as a bearing support for the stationary tubular connector.