The invention relates to an embedded NV-center diamond based magnetic field metering device. A nanometer diamond particle with a negatively charged nitrogen-vacancy(NV)-center is adopted as a sensitive element. Phase-shift micro-nano FBG (Fiber Bragg Grating) is adopted to be a sample cavity. Laser and microwave are utilized for controlling NV-center electronic energy level and magnetic field metering is realized through detecting the fluorescent intensity of the NV-center. The device provided by the invention has comparatively high spatial resolution and comparatively good stability and also has advantages of being small in size, low in cost and being compatible to room temperature operation. The device can perform metering on the surface of a to-be-meter object or in micro holes or gaps and is a magnetic field metering device based on solid atom spin. The device can be used for satisfying requirements for weak magnetic field metering with low cost and high spatial resolution in different field in the future.