The invention discloses a drink filling control method based on online parameter identification. Aiming at time-varying and nonlinear characteristics of a drink filling machine, servo travel of a filling server is intelligently adjusted according to the set filling amount and historical filling data in the method, so that the aim of improving the filling precision is achieved. According to the method disclosed by the invention, when a filling controller is designed, aiming at the problems in different phases of the filling process, an intelligent control algorithm is designed to automatically correct the filling error. In order to reasonably set parameters in the intelligent controller, the filling sensitivity of a drink filling system is identified on line according to the historical filling data, the compensation coefficient of the intelligent controller is modified in real time according to the identified sensitivity of the filling system, the filling precision is further improved, and the condition that the reject ratio is increased due to shake caused by excessive adjustment or due to insufficient adjustment is avoided.