A periodically poled KTiOPO4 (PPKTP) for second harmonic generation (SHG) with 9 μm period, 8 mm length, 3 mm width and 1 mm thickness has been successfully fabricated by applying an external electic field of high pulsed voltage. During the program, the real time monitoring measures such as electro-optical effect method, second harmonic generation two-dimensional method were used. 13.5 mW of 532 nm second harmonic generation green light was obtained pumped by 1 W, 1064 nm fundamental wave. The single-pass second harmonic generation conversion efficiency was 1.35% and the normalized conversion efficiency was 1.69% /(W·cm), which was close to the maximal theoretic value.