Geothermal gases taken from 10 hotsprings in the southern Jiangxi Province,SE-China,were analyzed for gas chemistry and isotopic compositions of helium,neon and carbon. The hotspring gases can be categorized into two types: The CO2-dominated type with CO2 concentration greater than 96.47% distributed in the southeastern part of southern Jiangxi,and the N2-dominated type with nitrogen higher than 91.04% located in the western part of southern Jiangxi. The δ13 C values of CO2 for the CO2-dominant type geothermal gases are -5.50‰ to -3.49‰(PDB) with a mean value of -4.66‰(PDB) showing that the carbon dioxide of the gases are originated from magmatic inorganic sources. The helium isotopic compositions of this type geothermal gases range from 1.36 to 2.27 Ra,indicating that up to 28.2% of the total helium is derived from the mantle. Relative He,Ar and N2 contents reveal that the nitrogen of the type of gases is the mixture of mantle-derived,crustal and atmospheric N2. Evidences suggest that the CO2-dominated geothermal gases belong to the mantle-derived inorganic type resulted from degassing of the mantle. The δ13 C values of CO2 for the N2-dominant type geothermal gases are -23.7‰ to -12.6‰(PDB) with an average value of -17.82‰,suggesting that the CO2 come from crustal organic sources. The 3He/4He ratios of the N2-dominant gases are from 0.06 to 0.13 Ra,representing input of radiogenic 4He in the crust. The 4He/20Ne- 3He/4He as well as He-Ar-N2 relations of geothermal gases demonstrate that the N2-dominant gases are of atmospheric origin with some crustal contributions.