The cloudtoground flash data (2004-2015) monitored by the Jiangxi lightning location system is analyzed,through the methods of statistics and linear regression to reveal the impact of different altitudes on lightning characteristics. The results show: (1) In Jiangxi Province,835% of lightning and 910% of positive lightning occurred in the plain and hill areas （with the total area being 74000 km2） and mountain area (the total area being 61000 km2） at the altitudes of 0 to 500 m above sea level. (2) The lightning density gradually decreases with the increase of altitude and the rate of change is different at the different altitudes; the current intensity of positive and negative lightning increases with the increase of altitude, and the rate of change is different at the different altitudes; the change of positive lightning is significant, and the variation of negative lightning is less than that of the positive lightning. (3)The proportion of heavy lightning area is the largest and the heavy lightning areas are basically in the southern Jiangxi; the heavy lightning and strong lightning areas are in the plain, hill and mountain areas with the altitudes ranging from 0 to 500 m; the weak lightning area is mainly in the mountain area with the altitudes ranging from 500 to 2200 m.