Biopolymers are widely used in surface modification of magnetic nanoparticles for biomedical applications. To improve the functionality of nanoparticles, it is of great significance to study the interaction mechanisms between these nanoparticles and biopolymers at the atomic level. Hence, in this study, the adsorption process of three different biopolymers (Gum Tragacanth, pectin and carrageenan) on Fe3O4 nanosurface was investigated through molecular dynamics (MD) simulations. In this regard, the adsorption process was first simulated under NVT (constant number of molecules, volume and temperature) condition. Then, the details of the interaction mechanisms between the biopolymers and Fe3O4 were comprehensively studied based on the interaction energies, concentration profiles and radial distribution functions. The obtained results indicated that all of the biopolymers were well adsorbed on the Fe3O4 surface, as a result of the interaction between Fe3O4 and the active atoms of the polymer chains. These interactions were mainly caused by hydrogen bonds formation and van der Waals forces. According to the obtained results, the strongest binding belongs to Fe3O4/carrageenan, followed by Fe3O4/Gum Tragacanth and Fe3O4/pectin, respectively.