The faults-enclosed oil/gas accumulation is controlled by faults, and the radioactive anomaly model above the oil/gas accumulation has its unique characteristics. Based on a discussion on the mechanism governing the formation of radioactive anomaly, this paper puts forward a radioactive anomaly pattern above the faults-enclosed oil/gas accumulation. An analysis of the radioactive anomaly characteristics of the radiometric profile above an oil accumulation in Yanji basin shows that the radioactive anomaly pattern above the faults-enclosed oil/gas accumulation does exist.