The bottom platen of an 800 ton hydraulic press, which was in operation in a ceramic factory, failed at the side supporting flange by fracture after 9x10(5) cycles under a maximum load of 530 tons. The platen material was cast steel 52. It was observed that the fracture started from a sharp corner of radius of curvature, 0.6 mm, at the flange-stem intersection. Design radius of curvature was specified to be 10 mm. Finite element analyses were performed on two models of the bottom platen, with radius of curvatures of 0.6 mm and 10 mm, respectively. It is observed from the results that stress concentrations developed at the flange stem-corner. Finite element analysis of the model with the design radius of curvature of 10 mm at the flange-stem corner resulted in satisfactory stress levels, but that of the model with 0.6 mm radius of curvature resulted in high stress concentrations and fatigue failure would occur.