Abstract: Based on analyzing the combination of geochemical indicators,the affecting degree of factors,the regional geochemical change,and the relationship between oil and gas,we establish the methods and effective combination of indica to rseries to search on natural gas exploration in Hang jinqi area of Ordos basin so as to analyze the region background and the preference of anomalies.The analysis of regional geochemical backg round,geochemical indicators high lighted in the law of space distribution reveals the abnormal and the intrinsic link between oil and gas,pointing out that the geochemical indicators of oil and gas abundance and low variability of the background belongs to the scope of non-uniform field;for the differentiation characteristics of hydrocarbons,the geochemical fieldin this area has the characteristics of the North-South Division:The hydrocarbons mainly come by the way of micro leakage in the south areas, in the north areas,the hydrocarbons gradually transit to the macro leakage.This indicates that the geochemical fieldis closely related to migration and accumulation of oil and also confirms that there is a more adequate gas source in this area.