In order to discuss the calculating methods of short term rigidity and bending deflection, ten precast prestressed concrete ribbed panels(PPCRP) with rectangular rib and two PPCRP with T-shaped rib were tested, and the load-deflection curves were obtained. The general formula of bending deflection taking into account the distribution of preformed holes in the rib and equivalent rigidity formula for PPCRP were deduced. The contrast analysis of load-deflection curves obtained from equivalent rigidity formula and test result show that short term rigidity of simply supported PPCRP under uniformly distributed load can be calculated at 0.85 times as equivalent rigidity.