Study of the effect of deep alkaline ground water on the soil properties was carried out in 5 districts, 13 counties of eastern and southeastern Hebei Province from 1978 to 1979. Results obtained showed that the nse of deep alkaline ground water in irrigation resulted in incrustation of soil and the decrease of crop yields. It was found that such ground water contained much soda, and its chemical characteristics such as soluble sodium percentage (SSP),residual sodium carbonate (RSC) and sodium adsorption ratio (SAR) were all much higher than the critical levels accepted internationally, Laboratory experiments showed that after irrigation with deep alkaline ground water for 2, 3 and 4 years, soil exchangeable sodium percentage (ESP) increased from 3.2% to 8.7%, 17.2% and 28.7% respectively, with an annual average increase of 5.8%. While soil pH increased from 7.5 to 8.6, 8.9 and 9.3 respectively, with an annual average increase of 0.48. As a result, soil physical property was deteriorated,and soil permeability coefficient significantly decreased from 5.45 mm/hour after irrigation with alkaline ground water for two years to 0.15 mm/hour for 4 years.Alkaline ground water mixed with saline water in a proper proportion has a good effect on prevention from deterioration of chemical and physical properties of soil. It is considered that the application of alkaline ground water mined with saline ground water for irrigation may be a economic and practical method for improvement of water quality, and it is of great practical significance for the improvement of salin-alkali soil.