Abstract: To obtain the optimal delay time of hole−by−hole pre−splitting blasting, based on Ansys / LS−Dyna finite element software, combined with field experiments, this paper studies the vibration attenuation law of hole−by−hole pre−splitting blasting under different delay time, which provides a theoretical basis for practical engineering application. The results showed that compared with the simultaneous initiation, the hole−by−hole initiation effectively reduced the peak particle vibration velocity (PPV), especially in the area near the pre−split trench. As the delay time increased, the K value of the Sadaovsk formula gradually decreased, while the α value did not change much. When the delay time was greater than 0.6T (T was the duration of single−hole blasting vibration), the values of K and α tended to be stable and close to single−hole blasting. The correction coefficient β was inversely proportional to the delay time, and the optimal delay time should be 0.6 T~1.0 T; the vibration reduction rate of the main blasting area after hole−by−hole pre−splitting was greater than that of the simultaneous pre−splitting blasting.