The invention discloses an emergency control method for a central air conditioner. The emergency control method comprises the following steps that a time domain simulation mathematical model is established; the parameters involved in the time domain simulation mathematical model are collected in real time; when a power system breaks down, an air conditioner host circuit breaker is disconnected; atime domain simulation mathematical model is solved by collecting parameters when the power system breaks down so as to obtain the maximum breaking time of the circuit breaker which does not influencethe comfort of the tail end room; the circuit breaker is allowed to close the host circuit breaker after the maximum breaking time is allowed, and the host current percentage is limited to be the host current percentage before control. According to the emergency control method, modeling and parameter identification are carried out on the refrigeration efficiency (COP), the chilled water, the fancoil and the tail end of the air conditioner host, an emergency control strategy for responding to the power grid control is provided, emergency control is carried out on the central air conditioningunit when the electric power system breaks down, so that the efficiency is improved, and the user requirements are met.