Spintronics,which utilizes spin as information carrier,is a promising solution for non-volatility memory and low-power computing in the post-Moore era.One important issue is to realize long-distance spin transport,together with efficient manipulation of spin current for novel logic processing applications.Here,we describe a gate-variable spin current demultiplexer(GSDM)based on graphene,serving as a fundamental building block of reconfigurable spin current logic circuits.The concept relies on electrical gating of carrier density and spin diffusion length in graphene4.As a demo,GSDM is realized in both single layer graphene and bilayer graphene.