Abstract: A miniature portable seismograph with its intrinsic design for safety,explosion proof is designed.The instrument has the characteristics of low weight,low power,high accuracy and high speed,and a 3 componented geophone is combined in it.As it can convert analog signals to digital datum and store the datum in original site,it has the extremely ability to resist the outside interference,increase the SNR of seismic signal,and reach the ideal condition of integrated sampling and effectively overcome the bottle neck effect of the general seismic data sampling system.This seismograph is best suited for high accuracy shallow layers multi wave exploration in complicated environment,such as testing the intensity of rock and soil block in site,prospecting the thickness of the residual coal and the engineering detecting etc.It is confirmed by field tests that this seismograph is practical and cost effective.