As North Shaanxi Slope in the Ordos Basin is a large smooth monocline dipping westward and the structure are simple, it has traditionally been regarded that the Triassic petroleum accumulation and distribution in the slope are mainly controlled by sedimentary facies, and therefore, the type of the accumulations are lithologic, on which structural and other geologic factors are believed to have no important effect. Nevertheless, as the exploration degree or drilling density is increased (the distance between wells are now 100 m to 200 m), the present authors find through structural mapping of high precision that the uplifts and nose-shaped uplifts in particular are acturally developed and have important controlling effect on the the Triassic petroleum accumulation and distribution in North Shaanxi Slope. And petroleum accumulations are especially enriched near the large nose-shaped uplifts. In fact, it has also been found that the formation and enrichment of the Triassic petroleum accumulations in the Slope are actually controlled by multiple factors, such as the background of nose-shaped uplift, sedimentary facies, the migration pathway, regional caprocks and hydrodynamics. Particularly, the background of nose-shaped uplifts is an important condition for the formation and enrichment of the Triassic accumulations; and the formation of the mid-large oil fields has close relations with such a structural backg round of nose-shaped uplifts. Consequently, the types of the Triassic accumulations in North Shaanxi Slope are complicated and multiple. Besides lithologic accumulations, the structure-lithologic and structure-hydrodynamic composite accumulations are possibly the mainly types.Therefore, the composite accumulations should be the major exploration targets in North Shaanxi Slope of the Ordos Basin.