In the underwater active polarization imaging method， it is necessary to mechanically rotate the polarizer in front of the camera to obtain the orthogonal polarization state images， which makes it difficult to output the de-backscattering video in real time. The method of real-time video output method for underwater active polarization imaging was proposed. Firstly， the orthogonal polarization switching position was changed from the camera side to the light source side， while the polarization state of the analyzer at the camera end remained unchanged， and it was proved that this change did not affect the effect of de-backscatter. Then， the arrayed orthogonal polarization light source was designed. The light source was composed of two groups of LED lamp beads with orthogonal polarization. The two groups of LED lamp beads were controlled by an independent drive circuit to output polarized light with orthogonal polarization state， and the mechanical structure of polarization state switching was eliminated from the hardware. Third， a synchronous control device was designed to control the polarization state of the light source output and the camera to take pictures， which realized the acquisition of orthogonal polarization state image data. Finally， the pipelined active polarization image processing method was used to realize real-time video output. The experimental results show that the proposed method can output the de-backscattering video in real time， and the performance of the de-backscatter is close to that of the mechanical active polarization imaging method. The deviation degree of the de-backscattering performance of the two methods is less than 4%， and the improvement factor of the image EME value is up to 17.96. This method has the advantages of simple structure， low cost， no influence on output frame rate， and wide selectivity of the camera， and can be widely used in the underwater imaging field.