It is of great significance to study the effect of repeated fluctuation of reservoir water level on the stability of slope. Considering the problem of water-rock interaction

uniaxial and triaxial compression tests were conducted on argillaceous sandstone at different dry-wet cycles

respectively. The results show that the deterioration degrees from high to low are as followed: peak strength

cohesion and internal friction angle. Meanwhile

the deterioration degrees of mechanical parameters increase with increasing the times of dry-wet cycles. In combination with Drucker-Prager criterion (D-P criterion) that widely used in geotechnical plastic mechanics

a new D-P yield criterion is put forward for argillaceous sandstone under different confining pressures and dry-wet cycles. By comparing the experimental value with the theoretical peak value calculated by the modified D-P yield criterion

the error is found less than 10 percent. Hence

the D-P yield criterion is feasible for argillaceous sandstone under dry-wet cycles in practical applications. This study provides a theoretical basis for yield strength of rock under the arbitrary confining pressure in practical engineering.