A scan driving circuit for OLED and a display panel are provided. The scan driving circuit for OLED comprising a plurality of scan driving units connected in cascade. The scan driving units at each stages for receiving the stage transmission signal at previous-stage, the first scan signal at previous-stage, the first scan signal at next-stage, the first clock signal and the second clock signal, and outputting a stage transmission signal at current-stage, the first scan signal at current-stage, the second scan signal at current-stage and the third scan signal at current-stage, wherein duty cycle of the first clock signal and the second clock signal are difference. The invention could generating three types shift scanning signal required for pixel compensation circuit and solved the problem of threshold voltage drift, then reducing difference brightness of display and enhancing display effect.