Based on the characteristics of mineralization geological background, resource geology and regional geochemistry, metallogenic potential of Porphyry copper (copper/gold) which locates in Sanjiang metallogenic belt of the east of Tibet was valued. Besides, several methods were employed to value the potential resources at different levels. All these discussion lead to the following conclusions: 1) considering the special geological structure , geochemical anomalies, porphyry and existing deposits (spot) distribution which shows a good state, Sanjiang ore belt in the east of Tibet has great ore resource potential. 2) The belt can be divided into five porphyry copper mineralization zones roughly: Yulong copper molybdenum zone, Gangda copper-gold zone, Tuoba copper- molybdenum zone, Leiwuqi-Dongda mountain copper molybdenum zone and Jiangda copper-gold zone. 3) Under the condition of 0.2% of copper cut-off grade, comparably, the storage resource of copper in this area ranges from 22 to 42 million tons and molybdenum from 0.45 to 2 million tons. And when the cut-off grade reduces to 0.1%, the storage resources of copper can reach up to 66 million tons. Through further geological work, about 25 million tons to100 million tons of copper can be acquired.