Abstract: In view of complex buried-hill reservoir characteristics and unknown controlling factors in the Shulu sag in the Jizhong depression, the controlling factors on the buried hill hydrocarbon accumulation and accumulating models were studied using petroleum geology and sedimentary petrology. After analyzing the buried hill types, reservoirs and transport systems, it is concluded that the sag has the foundation for forming diverse buried hill reservoirs. Then, the characteristics of diverse accumulation mechanisms were discussed in terms of hydrocarbon source rock, reservoir-cap assemblage and reservoir model. Finally, the controlling factors on various buried hill reservoirs were identified. The study shows that the effective floor is the controlling factor on the formation of the top-cut wedge-like buried hill reservoir, the basement oil source fault is the controlling factor on the formation of the buried hill reservoir in the uplifted fault block, and the lateral seal is the controlling factor on the formation of the fault terrace buried hill reservoir. It is proposed that the fault terrace and gully buried hills in the slope area are the most favorable types and zones for future exploration. The study is a useful reference to identification of buried hill targets and well locations in the Shulu sag, and helpful to make a new breakthrough in buried hill exploration.