Abstract: Gas logging is a logging method to find reservoirs by analyzing the hydrocarbon and other gas components in mud.The properties of a reservoir can be identified by the response of the oil,gas and water in gas logging.Since oil,light oil condensate gas reservoirs and gas reservoir properties are similar,it is difficult to distinguish the reservoir types by conventional logging data.In this paper,the discussion focus is mainly on the principle and application effect of the light hydrocarbon ratio method,PIXLER interpretation method,triangle plates and other methods,and other gas logging parameters to identify the reservoir types and fluid properties are also discussed.The gas logging method we proposed has good practical application effect in the study area.