The invention discloses a method for installing an engine rotor shaft, a connecting ring and blanking covers, and relates to the technical field of engines. The method for installing the engine rotor shaft includes the following steps that S1, the rotor shaft is installed on the connecting ring; S2, the front blanking cover is arranged on the rotor shaft in a sleeving mode and is fixedly connected with the connecting ring; S3, a first bearing is assembled on the rotor shaft, so that the rotor shaft, the front blanking cover, the first bearing and the connecting ring form an assembly; a bearing case is installed on an intermediate case, and a second bearing is assembled on the bearing case; S4, the assembly is moved to make the front blanking cover attached to the bearing case; and S5, the connecting ring is removed; and meanwhile, the rear blanking cover and the bearing case are fixedly connected. The connecting ring is used for the installing method of the engine rotor shaft. The blanking covers are also used for the installing method of the engine rotor shaft. The method has the beneficial effects that the demand of a high speed engine can be met, and rotors and stators can be installed quickly.