Organic/ferromagnetic spinterface plays a significant role in organic spintronics and the manipulation of spinterface will help to optimize the performance of molecular devices. Here, we systematically investigate how the magnetic anisotropy can be tailed by adsorbing different organic molecules on CoFe3N surface. It is found that the adsorption of C6H6, C6F6, and SC4H4 molecules on the FeCo-hollow site enhances the perpendicular magnetic anisotropy (PMA) of CoFe3N. The redistribution of Fe/Co d-orbitals near the Fermi level has an important effect on the modulation of PMA. Asymmetric SC4H4 adsorbed system has a larger PMA than symmetric C6H6 and its halide due to the hybridization between S p z and Fe d z2 orbitals instead of C atom. Our results indicate that appropriate organic molecule adsorption can improve the magnetic properties of ferromagnets, which benefits organic spintronic devices.