The invention discloses a multi-model integrated intelligent controlling method of a heavy-duty generator unit. The method comprises (1) constructing a model library and a controller library, wherein the model library comprises N submodels corresponding to the N operation conditions of the generator unit, the controller library comprises N submodel fuzzy controllers, each is designed a control rule corresponding to one submodel; each submodel fuzzy controller is the controller with double inputs and double outputs, the inputs are power angle deviation amount e delta and terminal voltage deviation amount u2, and the outputs are excitation regulation amount uf and valve opening regulation amount u2; (2) acquiring the real-time operating conditions data of the generator unit, and judging the actual operating conditions value based on the variable (delta, Vt); and (3) calculating the matching degree fn of the actual operating conditions value (delta, Vt) and N submodels in the model library, which is used as a weighting coefficient wn (n is an integer) of the integration of the integrated controller. The invention has the advantages of simplicity, good reliability, good real-time performance, high control accuracy, and good practical performance.