The utility model provides a fiber grating sensor-based weight measurement system. The fiber grating sensor-based weight measurement system is characterized in that the system includes a data acquisition module, a data transmission module, an optical signal receiving and transmitting module, a data processing module and a client end module, wherein the data acquisition module includes a fixing frame, a cantilever beam, sensor components and a suspension block; the fixing frame is of an L-shaped structure; the cantilever beam is horizontally fixed at one end of a vertical portion of the fixing frame, wherein the one end of the vertical portion of the fixing frame is far away from a horizontal portion, and the cantilever beam is perpendicular to the vertical portion of the fixing frame; the cantilever beam is of a slab structure and is an equal-strength cantilever beam; the sensor components are distributed at the upper surface and the lower surface of the cantilever beam; and the suspension block is fixed on one end of the cantilever beam, wherein the one end of the cantilever beam is far away from the fixing frame. The system is simple in structure; the data acquisition module is passive, so that long-distance placement can be supported, and the influence of temperature can be eliminated, and measuring accuracy is high.