Abstract: To solve the problem that parameters of accelerometers varied with time, a calibration method for accelerometers of in-field use was proposed. Resources in inertial navigation system(INS) was used rather than traditional calibration equipment, such as a precise turntable in this method.There was no need to unload INS from carrier in the calibration. The initial alignment obtained accurate gesture information and the Earth-s gravity was used as calibration standard. Non-linear optimization strategy was introduced to identify the zero bias,considering the non-linear property of the error model.Then the zero bias was used by the non-linear error model to transfer itself to linear .At last the linear least-squares method was used to identify the tri-axial non-orthogonal error and the scale factor error. The calibration key parameters would be achieved in this way. Simulation shows that measurement error is reduced by 20 times after the accelerometer was calibrated. Therefore the calibration precision indicates that this novel method is practical in-field use.