Recently Otsubo and Edamura reported that dielectric fluids showed striking viscosity increase on the application of electric field when the electrode surface was planted with hair-like short fibers. By using the phenomenon, ER effect applications are expected without ER fluids. This study aims to develop a fluid control valve with the ER effect caused by fiber planted electrodes. In this paper, firstly, the fiber planted ER valve, which have fiber planted high voltage electrode and normal surface ground electrode, is proposed. The valve can control fluid power with applied voltage. Secondly, as an application of a fiber planted ER valve, a 4-port fiber planted ER valve is proposed and fabricated. And then, it is demonstrated that a 4-port fiber planted ER valve can control a piston-cylinder.