Polyacrylonitrile (PAN) reinforced with nano-carbons such as graphene (Gr) and carbon nanotubes (CNTs) provides great opportunity for the development of low-cost and high-performance carbon materials. However, the poor dispersion and weak interaction between the carbon nanofillers and the surrounding PAN matrix prevent the final carbonized materials from reaching their full potential. Herein, we demonstrate a chemical approach using ethylenediamine (EDA) acting as a linker between graphene nanoplatelets and PAN for improved mechanical performance. The as-prepared CNFs exhibit a higher carbon yield and tensile modulus as well as improved graphitic structure compared to pristine PAN and PAN/Gr nanofibres. Furthermore, EDA can act as a N source for N-doping during the carbonization, enabling CNFs with hydrophilicity performance.