Exemplified by the utilization of geophysical data in search for a concealed iron deposit and based on the deduction and interpretation of the gravitational, magnetic and electrical cross-shaped profile data in a certain area, this paper sums up the train of thought and working methods for reducing the ambiguity in the geophysical anomaly interpretation. It is held that various kinds of constraint data should be accurately and completely collected during the field work and data acquisition so as to reduce the ambiguity, and that the one-by-one judgment and exclusive method seems to be an effective way for this purpose.