In order to investigate the dynamic response and stability of a steep slope under blasting vibrations from multiple blasts, the displacement, stress, maximum shear strain, safety factor and sensitivity of the steep slope were analyzed by field monitoring, numerical simulation and mathematical methods based on the an open-pit mine in Inner Mongolia. The data fitting results show that the radial vibration velocity has the highest correlation coefficient, with all the coefficients of three directions greater than 0.8. The relative error of the prediction results is larger in the near-blasting area, while smaller in the far area. After a single blast, the horizontal displacement increases rapidly and reaches the maximum value on the right side of the blast hole at 0.05 s. In the vertical direction, the stress increases gradually from top to bottom and the bottom is prone to stress concentration. The overall stress distribution of the slope gradually increases from the slope surface to the slope interior. After multiple blasts, the displacement and horizontal stress of the slope generally continues to increase with the increase of blasting times. The peak value of vertical stress and acceleration are generally oscillating with the increase of blasting times. For a period after the blasting, the acceleration is still not 0, and it takes a long time for the blasting energy to completely dissipate. Multiple blasting vibration will continue to reduce the safety factor of the slope to a certain extent. With the increase of blasting times, the change rate of the safety factor of the slope will gradually increase. Based on the gray correlation coupling analysis of safety factor and orthogonal tests, the sensitivity of each factor is as follows: charge per delay (X₅) > total explosive charge (X₆) > hole spacing (X₃) > blast distance (X₂) > blasting vibration duration (X₄) > hole number (X₁). It is indicated that in actual construction, it is necessary to control the charge per delay and total charge in order to ensure safe production.