The Bajiatan complex is located at the center of the Mesozoic Lujiang-Zhongyang volcano-tectonic depression. The feature of the volcanic dome is shown by geological mapping, gravitional and magnetic anomaly and landsat remote sensing photograpy. The study of petrology, mineralogy and geochemistry suggests that augite latite and augite monzonite are cognate, belonging to the upper and root parts of the volcanic dome respectively. Augite monzonite crystallized at high-temperature and over-hypabyssal conditions. The water-deficient, highly viscous magma was favourable to the formation of the volcanic dome. Study of geological data has revealed the evolutionary history of the Bajiatan volcanic dome.