The Baishachong and Beipaotai granites are both located in the eastern part of the Gejiu orefield, Yunnan province. In lithology, the Baishachong granite is mainly equigranular biotite granite, whereas the Beipaotai granite is mainly porphyritic biotite granite. In this paper, a systematic petrological, geochemical, and Nd, Sr isotopic study is carried out. On the basis of previous zircon SHRIMP dating, combing the new data obtained in this study, the characteristics, evolution and petrogenesis of the two granitic stocks are documented. The results show that the Baishachong granite is a highK calcalkaline peraluminous granite while the Beipaotai granite belongs to shoshonitic metaluminous granite. Both of the Baishachong and the Beipaotai granitiods are enriched in Rb, Pb and U; and depleted in Ba, Sr, Nb, P and Ti. The Baishachong granite shows a lower ΣREE, but stronger negative δEu anomaly than the Beipaotai granite. What’s more, the Baishachong granite reflects a tetradlike effect with a shape of “M”. Nd isotopic compositions suggest that the source of both the Baishachong and the Beipaotai granites are mainly derived in the crustal. Geochemical characteristics imply that both the Baishachong and the Beipaotai granites experienced a crystal fractionation process, while compared with the Beipaotai granite, the Baishachong granite experienced much stronger fractionated evolution process. The data of the Cretaceous granites around the Youjiang depression area located in southeastern Yunnan and western Guangxi Provinces, western South China, indicate that the granitic magmatism might be related to the lithospheric extension of the South China Block in late Mesozoic.