Abstract: Based on the geological characters in South Jiangsu area,the geological characters of coal-seam gases in Longtan Formation such as coal-seam characters (thickness, shape, texture, stability, distribution and coal resources), gas content, coal reservoir characters (storage space and rock absorptive characters), degree Of coal metamorphism,gas pressure,hydrogeological conditions etc. have summarized in order to provide geological bases for the present situation and exploration prospect of coal-seam gas resources in the Longtan Formation of the area and obtain knowledge according with Objective reality.