In this paper, a 532nm laser polarization underwater target detection information processing system is designed. Firstly, combined with GPS detection, the polarization characteristic data and location information of the underwater target are obtained by laser polarization technique. Then the polarization characteristic database is established on the basis of existing polarization characteristic data. Analyze and compare the measured polarization data with the existing polarization characteristic data so as to quickly complete the target identification and classification. Finally, use the acquired location and classification information to reconstruct three-dimensional model of the measured terrain and restore underwater scene vividly. The research of this subject is of great significance for the marine resources development, underwater engineering monitoring, submarine environmental monitoring and so on.