Water molecules and ions will be ordered arrangement hydrates under the electric field polar, which could change the water viscosity features.The effect of perpendicular electric field on the viscosity of the water was studied by laboratory experiment. The relationship curves between the experimental curve of electric field intensity were obtained by using constant head seepage and DC power supply system; the relationship between viscosity of water with ion concentration and flow velocity and other under the electric field was analyzed. The mechanism of water viscosity changing with electric field was detected basing the test results. The results show that the water viscosity is affected obviously by the electric field. The viscosi- ty of water s decrease along with the electric field sirength increase; Under the same field strength , the wa- ter is proportional to viscosity and ion concentration, and inversely proportional to flow rate.