A new drive laser system was developed to meet the requirement of DC-SRF-II photoinjector at Peking University. This modular drive laser system can operate from single pulse to 81.25 MHz CW mode, with green light output power 1.41 W @ 1 MHz. Longitudinal and transverse shaping were also implemented in the system, resulting in near flat-top 18 ps laser pulse with cut-Gaussian transverse profile. The stability measurement shows that the system output power stability is 1.8% RMS, and the pointing stability is less than 1 μrad.