The invention discloses a device and a method for measuring the micro vibration of an optical fiber. The device comprises a standard optical fiber and an optical fiber to be measured which are provided in parallel with each other and fixedly connected by an epoxy. One end of the standard optical fiber away from the optical fiber to be measured is connected to a light source, and the other end surface is polished to an end surface I inclined at an angle. One end of the optical fiber to be measured away from the standard optical fiber is connected to a spectrum analyzer, and the other end surface is polished to an end face II inclined at an angle. The standard optical fiber and the optical fiber to be measured are respectively provided with F-P cavities. According to the device and the method for measuring the micro vibration of the optical fiber, the sensitivity is high and adjustable, and the measurement of micrometer-level vibration of the optical fiber can be realized.