Abstract: In this paper,we based ours researches on the great deal of observation data on the hydrogeochemical effects,all of which were obtained from three surface explosions in the copper ore region of Yongping,Jianxi and two deep-well-explosions in Longhai,Fujian.It is believed that the explosive impulse force take an important role in various chemical changes in the components of Rn and other hydrochemistry.The effect of hy-drogeochemistry caused by explosions are necessarily associated with geological structures,hydrogeological conditions and geochemical environment in observation points.Based on this theory,the preseismic hydrogeochemical mechanism is discussed and studied.