The Dakao sequence of intrusion rocks is composing of Chaxiaochade tonalite, Zanaima biotite adamellite and Kangyong syenogranite. The single zircon U-Pb ages of Dakao intrusion is (169 ±4) Ma, indicated formed in Jurassic. The magma is evolved to be rich in silicon, alkali and aluminum. Rare earth elements are characterized by LREE enrichment, heavy REE flat. Trace elements characterized for enrichment in large ion lithophile elements of Rb, K, Ba and Th, but of Sr, Nb and Ta slightly loss; with εN_d(t) changes in the range of -7.6 ~-8.1, and with (⁸⁷Sr/⁸⁶Sr)i values of 0.709 69 ~ 0.711 04. Geochemical characteristics of Dakao sequence intrusion indicated it formed in volcanic arc setting and product of crustmantle mixing.