Abstract: In order to study the engineering properties of sodium polyacrylate modified red clay, sodium polyacrylate was used to cure the Liuzhou-remodeled red clay. The variable head permeability test and triaxial shear test were conducted to analyze the permeability and mechanical properties of the modified red clay, determine the optimum amount of sodium polyacrylate, and determine the disintegration resistance of the modified red clay by disintegration test, and reveal the microscopic mechanism of sodium polyacrylate modified red clay based on scanning electron microscope test. The results showed that the permeability coefficient of the modified soil decreased gradually with the increase of sodium polyacrylate, and gradually stabilized after reaching 3%, when the permeability coefficient was 8.1379×10⁻⁷ cm/s, which was 90.78% lower than that of the plain soil. In contrast, the shear strength of the modified red clay showed a trend of increasing and then decreasing, and reached a peak at 2%, which was 394.21% higher than that of the plain soil. So its optimal dosage is 3%, and the anti disintegration performance of the modified soil is improved by 42.86% with this dosage.The pores between the soil particles were filled by polymer chains, and the fragmented granular red clay became continuous. The arrangement structure and denseness were better than those of the plain red clay.The impermeability, mechanical properties and disintegration resistance of the red clay modified by sodium polyacrylate are significantly improved, which can provide theoretical guidance for practical engineering.