The ameliorative effects of rice cultivation (5~30 years) on soda saline-alkali soil in western Jilin Province of northeast China were studied through field survey and laboratory analysis. The results showed that compared with the virgin soil before cultivating rice, the pH value and the contents of total salt, exchangeable sodium, alkalization degree, the contents of CO₃^2-, HCO₃^-, Cl^-, Ca²⁺, Na⁺ and silt plus clay (<0.053 mm) fractions of soil decreased significantly after rice planting, while the contents of SO₄^2-, total organic carbon, water soluble organic carbon, humic acid carbon, fulvic acid carbon, alkali-hydrolyzable nitrogen and large aggregates (2~0.25 mm) in soil increased significantly. At the same time, the contents of alkyl carbon and alkoxycarbon in organic carbon increased whereas those of aromatic carbon and carbonyl carbon decreased in soil, resulting in an increase of the ratio of aliphatic carbon/aromatic carbon and a decrease of the ratios of alkyl carbon/alkoxycarbon and hydrophobic carbon/hydrophilic carbon. The above changes were usually more obvious with the extension of the rice planting years. The results indicated that rice planting could not only reduce soil alkalinity and salt content, but also increase the content and quality of soil organic carbon and improve soil structure. Therefore, rice planting was an effective way to ameliorate soda saline-alkali soil.