This paper illustrates the results of field tests conducted as a basic investigation of electroseismic phenomenon at the site of Kyushu University. The electroseismic phenomenon is a physical phenomenon in which electromagnetic response is derived by the incident elastic wave in the underground. According to Karl E. Butler, et al., mutual motion occurs between rock matrix and pore water by the propagation of P-wave in porous media. Spatial change in the water content per unit volume occurs, which is similar to the density change with the propagation of P-wave in elastic solid. Since the pore water with mobility can bring charges generated in the electrical double layer, the change in the water content agrees with the density change. Accordingly, domains of positive and negative overcharges are generated at the top of P-wave, which can be a current source. An electric field is generated between the domains. As a result of the field tests, it was confirmed that electromagnetic phenomena can be derived by the elastic waves. 2 refs., 8 figs.