1. Jilin Geological Exploration Institute，China Chemical Geology and Mine Bureau，Changchun 130022，China; 2. College of Earth Sciences，Jilin University，Changchun 130061，China; 3. Oil ＆ Gas Survey，China Geological Survey，Beijing 100029，China

Oil sands is an important unconventional oil and gas resources． At present，many oil sands deposits ( points) have been discovered in the oil sands mineralization belt in the western slope of Songliao Basin． In order to improve the efficiency of prospecting，based on extensive practice of oil sands exploration，combined with regional geology and exploration data，the authors comprehensively analyze and describe the geological characteristics of each oil sands deposit ( point) in the western slope，and summarize the ore-controlling factors and prospecting criteria． According to the mineralization and three-dimensional geological characteristics，the oil sand deposits ( points) are divided into two types and four styles． One type consists of the Xibeigou style and Changchunling style oil sands controlled by formation lithology，while the other type comprises the Tumuji style and Xiaotaipingshan style oil sands controlled by formation lithology and structure． The authors put forward a simple migration model of oil sands accumulation in the western slope of Songliao Basin，and delineate four favorable oil sands target areas in the central and southern part of the western slope．