Based on analyzing Surfer data format, the authors compiled the procedure for topographic correction. The topography could be corrected on the original presumed sectional drawing for plane observation, and thus the observation plane can be expressed in the form of practical elevation curved face, so as to attain the effect of being closer to the reality. The topographic correction on the sectional drawing is of symbolic significance. After topographic correction, the spatial shapes of anomalies and the spatial relationship of various anomalies can be more easily and objectively observed; meanwhile, the sectional drawing will become more beautiful and have higher practical indicating significance.