In this paper, the 3, 4, 9, 10-perylene tetracarboxylic acid-graphene (PTCA-G) composite was synthesized and the corrosion protection property of epoxy coating-coated Q235 steel containing PTCA-G composite was investigated. The results of Fourier transform infrared spectroscopy (FT-IR) proved that 3, 4, 9, 10-perylene tetracarboxylic acid (PTCA) and graphene (G) were combined via pi-pi interactions and hydrophobic forces between PTCA and G. The results of electrochemical tests indicated that with additives of sole PTCA, sole G and PTCA-G composite, the corrosion resistance of epoxy coating was increased compared with pure epoxy coating. And the most significant improved corrosion resistance of PTCA-G/epoxy coating might be attributed to the good dispersion and barrier performance of PTCA-G composite in the epoxy coating. Besides, compared with the corrosion protection property of PTCA-G/epoxy coating with other volume ratios, the corrosion resistance of epoxy coating containing PTCA-G composite with 10:4 vol ratio of PTCA and G was the best. It might be attributed to the excellent barrier and dispersion properties of PTCA-G composite with 10:4 vol ratio of PTCA and G.