At least some embodiments of disclosure provide a method and device for optical fiber monitoring and an optical fiber adapter. The method includes: a device for monitoring the optical fiber for performing optical fiber monitoring is installed in an optical fiber adapter and the optical fiber monitoring is performed by using the optical fiber adapter with the device for monitoring the optical fiber. The problem that the device for monitoring the optical fiber has complex wiring and a deployment position is limited is solved. And effects that the wiring complexity of the device for monitoring the optical fiber is reduced, and the deployment position is flexible and convenient are achieved.