The real time measurement of high current is an important guarantee of stable,secure,reliable and economical operation of the power system. An fiber Bragg grating (FBG0 current sensor is developed, which is mainly composed of current transformer and stack piezoelectric ceramic. The sensor transforms the measured high current through the current transformer into low DC voltage signal to load on the stack piezoelectric ceramic. Under the action of the inverse piezoelectric effect, the stack piezoelectric ceramic generates expansion and contraction, causing the fiber Bragg grating pasted on it to be deformed. By detecting the wavelength shifting of the measuring FBG and temperature compensating FBG, the value of high current can be measured by calculating the displacement difference of wavelength. The test results show that the nonlinear error of the current sensor is 7.27%FS (full scale), sensitivity is 0.056 7 pm/A, repeatability is 7.69%FS.