Abstract: There were different strength volcanic rock of three periods developing in the Shasan member of the middle of the eastern sag on Liaohe Basin and the volcanic rock were one of the important reservoirs. Through the study of the ages of volcanic rock extruding, the rock types, the reservoir's physical features and the fracture characteristics, it was considered that volcanic lithology is mainly trachyte, basalt and tuff, there into the reservoir lithologies are mainly trachyte, the physical character of the matrix was not so good and became the advantageous reservoir rebuilt by the later tectonic movements. The classifing standard of volcanic rock reservoir was built.It was considered that the advantageous reservoir were mainly distributed on tectonic broken belt, the thickness was between 20~200 meters.