The distributed optical fiber acoustic wave and vibration fusion sensing system of the present invention includes a laser, a 1×2 optical fiber coupler, an acousto-optic modulator, an erbium-doped optical fiber amplifier, a first optical fiber filter, an optical fiber circulator, a first optical switch, Optical fiber Raman amplifier, second optical switch, second optical fiber filter, 3×3 optical fiber coupler, first photodetector, second photodetector, third photodetector, data acquisition and processing unit, computer, host machine software. Advantages: The system combines two sensing functions and modes of vibration and sound wave sensing, which can meet different work requirements, effectively overcome the shortcomings of conventional distributed optical fiber sensing equipment with only single vibration or sound wave sensing, and save costs , is an important technical improvement in the field of distributed optical fiber sensing; it can be flexibly switched according to different usage requirements and scenarios, saving costs and easy to use; it proposes a way to control the optical switch to switch between vibration and acoustic sensing modes, and the operation is flexible.