To detect very small abnormal set of a workpiece to a forming surface.

A press forming apparatus 10 is changed into a state where the workpiece can be set to or taken out of the forming dies and a state where the workpiece can be formed with the forming dies by driving at least one side of a pair of forming dies (20, 32). On the forming die 32, a fluid flow passage 30 one end of which is opened to the forming surface 24 and the other end of which is connected to an outside fluid supply source 44 is formed. The apparatus further includes a detecting means 46 for detecting whether the fluid pressure in the fluid flow passage 30 exceeds the predetermined pressure.