Abstract: Small-interval tunnel is widely used in the design of highway short tunnel because it has the advantages of relatively low cost and conducive to overall linear optimization. The construction process of small-interval tunnel is simpler than that of the double-arch tunnel. However, in view of the relatively small thickness of middle rock wall in the tunnel, in the construction process of drilling and blasting method, blasting will not only affect the stability of surrounding rock of tunneling tunnel, but also has a certain impact on the structural stability of adjacent tunnels, and further affects the safety of tunnel construction. Taking the small-interval tunnel Shiwei tunnel as an example which is under construction, during the blasting construction of the right tunnel, through the blasting vibration test of the left tunnel according to the measuring points at different distances from the blasting face, the variation law of vibration wave velocity of the surrounding rock and its structure of the left tunnel after blasting vibration is studied. According to the monitoring results and analysis of blasting vibration, the blasting scheme and parameters can be dynamically adjusted to ensure the safety of blasting construction. The research results of blasting vibration law of Shiwei tunnel have certain reference significance for the blasting construction of highway tunnel with small clear distance and short distance.