The selection and the determination of mechanical parameters are closely related with the stability analysis of laneway and slope in mining engineering. The spot test method to obtain mechanical parameters of rock mass based on the engineering practice is restricted by many environment conditions and technique conditions and is also very costly. Because the blasting disturbance is the most important factor influencing the slope stability for a practical open-pit slope, it should be taken into consideration in the determination of mechanical parameters of slope rock mass. In general, this factor is often ignored in the Hoek-Brown standards for processing the results of indoor rock testing in line with the actual conditions. To address this problem, the nonlinear equation is applied to obtain the relationship between the modified coefficient under disturbance and the integrity coefficient. In this paper, the modified expressions of Hoek-Brown strength criterion, in consideration of the blasting disturbance, are applied to the east slope of the East Gebi open-pit. It is shown that the method in this paper gives good results.