The utility model relates to the technical field of power, and in particular relates to a magnetic rheologic flexible motor. A stator is arranged in a casing. A fan sleeves a rotor. A rotor bearing is embedded into a rear end cover. The rear end cover and the casing are fixedly assembled and connected. The rotor is inserted into the rotor bearing and is connected with the casing. An output shaft is sleeved into a power shaft seal plate. An O type seal ring is sleeved into a power shaft. The power shaft seal plate and the power shaft are fixedly assembled and connected. A skeleton oil seal is embedded into the power shaft seal plate. A magnetic steel block is embedded into a power shaft bracket. A medium bearing is embedded into the power shaft bracket. A medium bearing press plate is close to the medium bearing and is sleeved and limited on the power shaft bracket. The power shaft bracket is sleeved into a front end cover and is close to a positioning sleeve. The power shaft is sleeved into a rotor shaft. The front end cover and the casing are assembled and connected to form a whole body. The magnetic rheologic flexible motor provided by the utility model has the advantages that the properties of a magnetic rheologic material are applied to the technical field of the motor; a power flexible output function is realized; the problem of safe motor start is solved; and the magnetic rheologic flexible motor has the advantages of large output, small volume, simple structure and the like.