Abstract: In order to understand the physical, mechanical and engineering properties of alkali residue: a special soil mass, and summarize its hydrogeological characteristics, a large number of indoor physical tests: direct shear tests and permeability tests are carried out on the soil samples obtained by geological drilling from an alkali residue filling site in Tianjin Port, and field vane shear tests and standard penetration tests are carried out on the alkali residue layer. The physical and mechanical parameters of the alkali residue soil are measured. The hydrogeological parameters (permeability coefficient and radius of influence) of the alkali residue aquifer are measured by field tests (pumping test, water injection test and double ring seepage test). The test results show that the alkali residue soil has the characteristics of both mucky soil and sandy soil, which is similar to silty sand silty sand and belongs to the aquitard. The influence radius of pumping is basically consistent with the calculated value of the theoretical formula, and the theoretical formula of pumping test is applicable to the alkaline residue aquifer.