Abstract: Oil and gas geochemical exploration technique is a direct deploration technique based on the detection of the subtle matters dominated by hydrocarbon gases. With its unique advantages of being quick, effective and cheap, this technique can play a positive role in natural gas exploration. By means of study of the characteristics of the geochemical indicators and their anomaly distribution regularities over the typical known gas reservoirs, the most suitable geochemical indicators and methods for natural gas exploration were proposed. And by taking Xinchang Gasfield as an example, the authors explored the formation of (geochemical) anomaly provides additional supports for the effectiveness of the oil and gas geochemical exlporation technique in the expolration for natural gas.