We investigate the spin-filter effect in double parallel quantum wires (QWs) coupled with ferromagnetic leads on a graphene sheet.The dependences of the wire-graphene coupling strength, as well as the spin polarization of the ferromagnetic leads are studied explicitly.It is found that the vire-graphene coupling strength tends to reduce the current and suppress the down-spin current more severely.The spin polarization strength can have a reinforced (subdued) effect on the up-spin (down-spin) current under the parallel alignment, and an identical effect under the anti-parallel alignment.Such differences can stimulate obvious spin-filter and tunnel magnetoresistance (TMR) effect, which possesses a positive plateau (negative dip) structure around zero bias voltage.Our results suggest that such a theoretical model can stimulate some experimental investigations about the spin-filter devices.