Graphene oxide was obtained to prepare polyacrylonitrile/graphene oxide (PAN/GO) composite nanofibers by electrospinning method. A series of PAN/GO composite nanofibers was prepared with different mass fraction of graphene oxide. The scanning electron microscope (SEM) and the transmission electron microscopy (TEM) were used to observe the microstructure of the composite nanofibers. And then study the thermal performance of the composite nanofibers via the differential scanning calorimeter (DSC) and the thermal gravimetric analysis (DTA). Finally computer-controlled electronic universal testing machine was used to study the mechanical properties of the composite nanofibers. The results show that when the graphene oxide was added

the PAN/GO composite nanofibers become thin and the thickness uniformity of the nanofibers was affected. The oxidation of PAN was suppressed because of graphene oxide. The mechanical property of PAN was increased with graphene oxide added. The breaking strength of PAN was doubled when the mass fraction of oxide graphene was 0.1%

but the breaking strength was reduced when that was 1%. According to the experimental results the mass fraction of oxide graphene at 0.1% was better.