Enclosed is an electrode for a flow battery, which comprises a graphite felt (1), wherein: said graphite felt includes multiple flow channels (2) for transmitting an electrolyte, said flow channels (2) are straight and distributed at equally spaced intervals, and the width and depth of said channels (2) and the interval between adjacent flow channels (2) are each half of the thickness of the graphite felt (1), which is a polyacrylonitrile graphite felt (1). Said flow battery electrolyte has a simple structure and is easily processed and assembled, the flow battery thickness and internal resistance are low, and transmission and dispersion of the electrolyte is highly effective. Flow batteries using said electrode enjoy high power density, high energy efficiency, long life, and can be made into high-power or even super-high-power flow batteries.