The invention discloses a vibration-ultrasound broaching machine for key parts of an aero-engine and a broaching method of the vibration-ultrasound broaching machine. An existing broaching machine formachining the key parts of the aero-engine is poor in chip breaking capacity. The vibration-ultrasound broaching machine for the key parts of the aero-engine comprises a broaching machine body and aworkbench. The broaching machine body comprises a broaching machine drive assembly, a lathe bed, broaching machine guide rails, broach clamping assemblies and an ultrasound broach. The ultrasound broach comprises an ultrasound transducer, a broach body and broach clamping sections. The workbench comprises a bottom platen, an upper platen, a two-axis drive assembly, an R-direction drive part, a vibration assembly, a mounting disc and an auxiliary clamping assembly. The vibration assembly comprises a swing shaft, a vibration motor, spring limiting assemblies and a swing platen. The spring limiting assemblies comprise swing spring, limiting columns and limiting nuts. As vibration and ultrasound are combined, high chip breaking and discharging capacity is achieved on the broaching machine.