In field geological survey, the hand-held GPS should be correctly calibrated so as to guarantee the measurement precision. In the work district, the authors uniformly selected 2-3 control points and then correctly input the central longitude and such correction parameters as DX、DY、DZ、DA and DF to fulfill the operation. The authors have conclude that the ratios between the changing rates of the GPS display coordinate X, Y and the changing rates of the correction parameters show certain linear relationship in a certain area. Based on such a linear relationship, the equation-solving method can be used to determine DX、DY and DZ parameters rapidly and accurately. In addition, different DX、DY and DZ combinations can all be used as the proper correction parameters so as to accurately correct the GPS so long as they can satisfy the solution of the equation set.