A novel magnetic mesoporous carbon nitride (MMCN) adsorbent with large surface area has been synthesized by a chemical precipitation method, and characterized by X-ray diffraction pattern, transmission electron microscope, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, zeta potential, and magnetic hysteresis loop measurements. Kinetic results revealed that the adsorption equilibrium of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) on MMCN was achieved within 180 min, and the adsorption process followed the pseudo-second-order kinetic model. Adsorption isotherms fit well to the Langmuir model, and the maximum adsorption amounts of PFOS and PFOA on MMCN were 454.55 and 370.37 mg g(-1), indicative of a more favorable adsorption of PFOS by MMCN than PFOA. The difference of adsorption amount of PFOS and PFOA on MMCN was ascribed to the different functional groups of PFOS and PFOA. Moreover, adsorption of PFOS and PFOA on MMCN was spontaneous and endothermic in nature. The adsorption mechanisms of PFOS and PFOA on MMCN could be attributed to electrostatic attraction and hydrophobic interaction. Furthermore, MMCN was readily recovered in an external magnetic field and still maintained high adsorption capacity after five-times recycling tests.