Clarifying the dynamic response characteristics of mortar bolts under the action of tunnel blasting and excavation and ensuring the safety and stability of the bolt support system is the key to the efficient construction and safe operation of the tunnel.Based on the Longnan Tunnel's surrounding rock blasting excavation engineering at all levels， using the dynamic finite element numerical simulation software ANSYS/LS-DYNA， the dynamic finite element calculation models of mortar bolt blasting excavation for different surrounding rock levels and different grouting ages are established and analyzed. The dynamic response characteristics and failure mechanism of mortar bolts at various locations under the action of tunnel blasting. Studies have shown that during blasting and excavation of surrounding rock at all levels， the vibration speed and axial force of the anchor rod on the tunnel vault are the largest， and the end of the anchor rod is the most dangerous point. Along the tunnel axis， the vibration speed and axial force of the anchor rod decay continuously as the blasting distance increases. The peak vibration velocity of the bolt at each part decreases with the increase of the grouting age， the axial force will decrease with the increase of the grouting strength， and the sheer force will also decrease. The axial force value of the dome anchor rod has a linear relationship with the peak vibration speed， and its surrounding rock grade and age are related. According to the safety axial force of the bolt， the safe control vibration speed of the mortar bolt in tunnel blasting excavation of different surrounding rock grades and different maintenance ages can be calculated.