Abstract: Based on the geochemical characteristics of soil-gas-hydrargyrum measurements combined with other geochemical exploration indexes and characteristics of petroleum geology, the integrated studies were made on Lishu Depression, in Songliao Basin in this paper. Thereafter, analyses of soil-gas-hydrargyrum are carried out in a certain research area, with 384 sampling points in which 80 points are abnormal with a probability of 20. 83%. Most of the abnormal measurement points are clustered: 1)The abnormal points of the northern part of the research area are clustered in Shiwu-Sangshutai Fault Block and No. 1, 2, 3, and 4 abnormal blocks; 2) The abnormal points of the southern part of the research area (4 controlling lines) concentrate at Shenyang, Kaoshantun, Yushutai and Shuang shan-Xinglitun in which oil traces and spots are observed at depths of 400-500m proved by drilling at No.4 Abnormal Block. (Xiaokuanwobao).