Provided is a bone conduction hearing aid device, including: a housing, a piezoelectric vibration assembly and a vibration transmission element, the piezoelectric vibration assembly and the vibration transmission element are both arranged in the housing, a first end of the vibration transmission element is connected with the piezoelectric vibration assembly, a second end of the vibration transmission element is connected with the housing, and the housing includes a vibration output portion that outputs vibration through contact.