Abstract: The Baochu slope in the Xihu Sag, deposited in Cenozoic, is a large slow slope belt.The Slope has complex and unique framework of sedimentation and structure. In this paper, the gelolgical conditions of the Paleogene (formations of interest) in the Baochu slope is empatically recounted. The results from analysis of hydrocarbon system that are drilled areas (Pinpzhong and Pingbei)are the prolilic areas for the oil/gas accumulating, and the undrilling areas (Pingnan, the Haijiao bay and Ying Cuixuan) are predicted as the hydrocarbon potential areas.