Graphene oxide (GO)-vulcanized polyacrylonitrile (SPAN) composite was developed by mixing additive GO powder with SPAN powder by ultrasound. Its performance was evaluated in Li-S battery with ether-based electrolyte. Surprisingly the pure SPAN cathode is unstable in ether-based solvent compared with in carbonated solvent, unless a certain amount of GO is added. Due to its unique layer-structure, GO could function as the barriers, which could limit the agglomeration of SPAN composite and reduce the dissolution of sulfur accompanying the electrochemical reactions. With the additive of GO, the maximum cathode capacity of 275 mA h g^-1 is higher than that of either GO or SPAN alone. This composite cathode possesses high capacity even at high current density of 1.5 A g^-1. More importantly, the composite cathode is stable for 500 cycles of discharge/recharge.