Investigation and field experiment on the water and salt regime of paddy soils were carried out in the depression area along the Yellow River in Fengqiu county, Honan Province. The results obtained are as follows: 1. Because of the light texture of the soils from sandy loam to loam, salt injury was resulted from the high capillary conductivity of soil water and the readily accumulation of salts in the surface soil, even under the condition of low concentration of ground water. The submerged water in rice field could wash the salt downward, and was also conducive to the desalination of the ground water.2. Secondary salinati}on of the soils around the rice field was caused mainly by the rise of ground-water level due to the irrigation of the rice field. The outward spreading of secondary salivation of soils was induced by the high ground-water level of this adjacent area as compared with that of outer area, i.e., by the occurrence of a hydraulic potential gradient in the surrounding soils of rice field. The water and salts in soil moved from the place adjacent to the rice field with higher hydraulic potential to places far from the rice field with lower hydraulic potential, and were accumulated there.