Abstract:Objective: To establish a method of TLC identification for Dida commonly used in Tibetan medicine from different species. Method: With silica gel G as the stationary phase, and chloroform-methanol (40:1) as mobile phase, oleanolic acid from different species of Dida was separated and identified. Result: Oleanolic acid was detected in 70 kinds of Dida derived from the Gentianaceae Swertia, Halenia, Gentianopsis, Lomatogonium, and Saxifragaceae saxifrage, except for the saxifrage, there are some differences among different genera or subjection. Conclusion: This TLC method can be used for identification of oleanolic acid in Dida from different species except saxifrage.