This paper established regional ore-forming potential indicator (ROPI) modeled by digital model of ore deposits. It can be used in regional mineral resources quantified prediction and evaluation. Meanwwhile, ROPI can be used in the study of ore deposit time hierarchy. Using ROPI in regional resource potential evaluation to three main commodities in north zone of Sanjiang in southwest China has been preceded. At the end, this paper predicted mineral resources of study area. The ROPI calculation results of main minerals are below. Lead-Zinc deposits: weight: N-3, E-12, K-40, J-15, T-3 (T-3-26), Pt-2-1, others-1. ROPI: N-288, E-120, K-600, J-525, T-288, T-3-3588. Copper deposits: weight: N-6, E- 19, K- 18, J-24, T-28, others-1. ROPI: N-534, E-475, K-216, J-864, T-2492, T-3-3108. Silver deposits: weight: N-8, E-18, K-44, J-10, T-8 (T-3-10), others-1. ROPI: N-368, E-216, K-440, J-230, T-368, T-3-510. According ROPI ordering, Cretaceous and upper Triassic strata are most favorable ore-forming place for Pb-Zn and Ag in studying area; Jurassic and Triassic are most favorable for Cu.