To elucidate the binding mechanism of graphene oxide (GO) with bovine serum albumin (BSA) at molecular level, it is urgent to investigate their interactions in this work. The results indicated that multi noncovalent forces including hydrophobic force, hydrogen bonds, van der Waals and pi-pi* stacking interactions were involved in the adsorption forces of BSA on GO surface. The kinetics of BSA adsorption onto GO follows the pseudo-second-order kinetic model and was a fast process with high adsorption capacity. Some structure and functions of BSA were changed by GO binding. The decrease of melting temperature (T-m) and enthalpy changes (Delta H-m) implied that BSA on GO surface is more prone towards thermal denaturation. Drug competition experimental results showed that the binding affinities of BSA with 1-anilinonaphthalene-8-sulfonic acid (ANS) and ofloxacin (OFLX) were decreased to some extent. The esterase-like activity of BSA was obviously increased and BSA became more glycosylated in the presence of GO. Interestingly it was found that presence of GO significantly induced the conformation and activity changes of BSA. This work should help readers to understand and develop ideas for bio-related applications and to discuss the toxicological effects of graphene materials. (C) 2017 Elsevier B.V. All rights reserved.