The main frequency of vibration is an important parameter for evaluating the harm of the vibration of blast seism,which will inflence the monitoring to the vibration rate of particle mainly by the response of self-vibration frequency of such facilities as slope,dam,underground structures and buildings.This paper introduced that long hole blasting near slope was simulated and the influence of the main frequency of vibration on the measurement of the vibration rate of particle was studied with CD-1 velosity transducer,presented empirical formula on experimental condition and explained the application principle in practice on site.