In this paper, theoretical analysis is performed on the influence of multiple piezoelectric effects on piezoelectric coefficients. And a kind of classical piezoelectric ceramics was adopted to conduct the experimental validation. The experimental results of short-circuit boundary condition are obtained by the methods that a capacitor whose capacitance is much larger than that of the stack is parallel with PZT-5. Influence results are obtained through comparing them with open-circuit piezoelectric coefficient. Experimental result shows that multiple piezoelectric effects make piezoelectric coefficient of PZT-5 be altered by 18%.