The invention discloses an optical fiber Fabry-Perot sound pressure sensor manufacturing method based on a graphene membrane and a measuring method and device thereof. A sensor is manufactured based on the graphene membrane and the optical fiber Fabry-Perot interference optical principle. Firstly, a single mode fiber is rinsed and processed, the graphene membrane is transferred, and the graphene membrane is adsorbed to a zirconium oxide single mode inserting core; then, the zirconium oxide single mode inserting core is inserted into the processed single mode fiber from the other end. Therefore, two reflecting surfaces of Fabry-Perot interference are formed by the end face of the single mode fiber and the graphene membrane, an optical fiber-air-graphene membrane interference cavity is formed, an interference cavity length detecting device is set up, interference spectrum signals are demodulated by using a two-peak method, and the high sensitivity detection of weak sound pressure signals is achieved. The sensor has the advantages of being simple in manufacturing, high in sensitivity, small in size, resistant to electromagnetic interference and the like, the problem that a sensor is low in sensitivity due to the limitation of the reduction of the thickness of a membrane in the prior art is solved, the sensitivity of the membrane type sound pressure sensor is improved, and the sensor can be expected to be applied to the underwater sound field, the electroacoustic field, medical field, biomedical engineering filed and the like.