Proposed in this paper is an underwater photogrammetry system for towing test,which is based on the principle of close-range photogrammetry.In this system,two underwater cameras are installed on the towing carriage to take photo synchronously in a certain frequency,and the obtained photos are processed in terms of image recognition and coordinate calculation.Thus,the movement trajectory and the attitude of the towed object is obtained.The system is a non-contact measuring method with simplicity and feasibility,which does not damage the measurement target and destroy the natural state of measured objects.Test and error analysis results show that the developed system is of high measurement accuracy,and that it is a reliable and convenient measuring method.