Based on the principle of division-of-amplitude laser polarization state detection, a new dynamic detection system for laser polarization is designed. The incident laser is made into three light paths which can change the beam polarized direction, polarized beam splitter, half-wave plate and polarized beam splitter, polarized wave plate and polarized beam splitter. The light intensity power value of outgoing beam is detected. Polarization state of the laser to be measured is shown in Labview custom coordinate system. The measurement results show that the polarized states of linear polarized light, circular polarized light and elliptical polarized light are spindle-shaped, circular, elliptical. With the change of incident laser polarization state, the detection results will change dynamically.