The invention belongs to the technical field of video monitoring, and relates to a swimming pool drowning monitoring and detection method by using a camera to detect a drowning behavior possibly happening in the swimming pool. The method is realized in a monitoring and detection device which is composed of a computer processing system, a camera, a polarizer, a posture detector, a caller, an LED monitor, a signal receiver and a waterproof cable. The method mainly comprises the following steps of detection system starting, target matching monitoring, foreground detection, target tracking, targettracking and positioning, drowning judgment and drowning alarming. Timely processing can be carried out according to the information photographed by the camera, a drowning situation is analyzed, processing and alarming are carried out, the device cost is low, mounting and maintenance are easy, the system is safe and high-efficiency, the positioning is accurate, the calculation is scientific, drowning pre-judgment and alarming can be carried out in all directions and at multiple angles, the error rate is low, a life can be saved at a first time, and the safety of the swimming pool is greatly enhanced.