The appraisal of geophysical prospecting anomalies has previously been car ried out on the qualitative basis. In accordance with the characteristics of a skarn type magnetite deposit, this paper presents a quantitative comprehensive appraisal model for magnetic anomalies in the ore district mbiguous compre hensive appraisal model of subordinate function method, and also puts forward a new parameter Are certainty μ=C·B/T (where Cstands for matrix of coeffi cients, and B'Tfor the transposition of the comprehensive appraisal subordinate degree matrix B') as the criterion for final appraisal. Tests show that the accu racy of this appraisal model reaches 84%.