An industrial fibreglass winding process is employed to apply graphene based sizing (0.2 wt% graphene concentration) on fibreglass surface. Both SEM and Raman spectroscopy characterization have proved that the coating of graphene on fibreglass surface is honzogeneous and that the roughness of the fibreglass surface was improved. Long fiberglass-graphene reinforced PA66 pellets are successfully prepared through a pultrusion process. LGF-graphene-PA66 composites are produced following an injection molding process. Thermal conductivity was found to increase from 0.23 W/m.K-1 to 0.67 W/m.K-1 when compared with samples without graphene coating. The tensile strength of LGF-graphene-PA66 is 196 MPa while that of LGF-PA66 is 173 MPa. Tensile modulus is also found to increase to 13.5 GPa from 10.6 GPa after graphene coating. This new graphene coating process is a good method to produce high performance composites.