With a measurement system for power and nonlinearity calibration,a suit of calibration facility to measure optical fiber power meter has been established in this paper. The nonlinearity coefficient of optical fiber power can be measured with triplet superposition method. The wide spectrum fiber power meter accuracy is largely increased by cryogenic radiometer,silicon trap detector,thermopile detector coop-eration. The optical input interface is solved by a conversion clamp. A special method is adopted in this software to eliminate the optical power drift and the fluctuation of zero power point in order to improve the measurement accuracy. The detailed measurement uncertainties are estimated and a conclusion is also made.