Accor ding to the set theor y ( int er section ) of mathematics and the theory of " multie-lement inform ation water supply sur vey ", this paper established the log ically infer ential model of wat er supply sur vey in the w ater deficient hill country in Zhenjiang. By means o f g eo log ic remot e-sensing r esear ch, g eohydrologic and tect onic ex aminatio n and g eophy sical synthet ic prospecting , the author s gr adually acquired the inform ation about the watery blocks, w ater storag e g eolog ic body , w ater stor age tectonics and idio graphic placing of w ells fr om reg ion→section→po int. T hr ough the pr actice of water supply sur vey, the author s confirm ed the adv antages o f " multi-element information theor y " in w ater-supply survey in w ater-deficient hill country of the complicated tect onics. Simultaneously , the authors also recommended the practical problems that must be paid attention to during the pro cedur e o f making use of "multielement info rmation theor y" .