The invention provides a drowning prevention system, swimming pool, method and teaching method. The drowning prevention system is arranged in the swimming pool and comprises a plurality of first wireless signal transceivers, one or more wearable devices with second wireless signal transceivers, a control terminal and an audio broadcast device. The drowning prevention system, swimming pool, method and teaching method has the beneficial effects that multiple drowning judgment logic is achieved, and accurate drowning information can be provided under a complex environment, so that the timeliness and reliability of rescue are guaranteed; assembly modules can operate in an integrated systematization mode and also can operate and work independently, and it is guaranteed that when any functional module unit loses efficacy, drowning judgment and position tracing of a swimmer are not affected, so that the system is safer and more reliable; and each function module provides the position basis for the controller system, and then the controller system obtains the precise position and the drowning judgment according to logical calculus, so that the phenomena of position drifting and a system drowning judgment error caused by the external environment influence are overcome, and accurate positioning can be realized at any time.