In order to make clear of the reservoir-forming laws of Heidimiao oil reservoir in west Daqing Placanticline of North Songliao Basin, the studies on high-resolution sequence stratigraphy, sedimentary facies and sandbody distribution are conducted. By means of seismic drilling, well logging and another data, there are three sub-sequence sets and twelve subsequences are recognized in No. 2 and 3 members in Nenjiang Formation. The studies show that the sandbodies in Heidimiao oil reservoir are featured by the development from top to bottom and from east to west, 4 favorable hydrocarbon accumulation belts and 1 play are predicted in Heidimiao oil reservoir.