The invention provides a method and system for a blast-induced vibration monitoring of a tunnel in high asymmetric in-situ stresses. According to the method, triaxial vibration sensors are respectively fixed in areas having different radial depths inside surrounding rocks of a stress concentration area behind a tunnel face of the tunnel in high asymmetric in-situ stresses, and each triaxial vibration sensor monitors blast vibration velocity and acceleration at a position thereof. The system comprises a plurality of triaxial vibration sensors which are fixed in areas having different radial depths inside surrounding rocks of a stress concentration area behind a tunnel face of the tunnel in high asymmetric in-situ stresses, and each triaxial vibration sensor is used for monitoring blast vibration velocity and acceleration at a position thereof. The method and system can improve the safety and the efficiency of tunnel excavation construction.