This paper deals with the effect of the concentration of sodium bicarbonate in groundwater on the alkalization of soils with different texture. According to the data from soil equilibrium experiment in laboratory, the results are summarized as follows: (1) The concentration of sodium bicarbonate in groundwater which could induce the alkalization of soils was more than 0.lg/l, and the concentration which could induce the formation of solonetz was 0.4g/l. (2) Soils with different texture adsorbed different absolute amounts of sodium from sodium bicarbonate solution of same concentration. The quantity of absorbed soodium by clay soil was more than that by silt loam, but their soil ESP were similar. (3) There was a positive correlation between the dissociated sodium and exchangeable sodium of the soils. (4) It was also found that there was a good correlation between the pIi and ESP of the soils.