A novel pyridinium-diethylenetriamine magnetic chitosan (PDFMC) has been prepared and used for magnetic separation of Cr(VI) from aqueous solution. The PDFMC was characterized by using an X-ray diffractometer (XRD), a Fourier transform infrared (FTIR) spectrometer, a thermo gravimetric analyzer (TGA) and a scanning electron microscope (SEM), while the magnetic property was examined by the magnetic property measurement system magnetometer (MPMS). The PDFMC worked well on removal of Cr(VI) in any condition of acidic, neutral and basic solutions with the capacity (qmax) of 176 mg L-1 (at pH 3, acidic), 124 mg L-1 (pH 6, near-neutral), and 86 mg L-1 (pH 9, basic) based on the Langmuir isotherm model. Kinetics study showed that the removal of Cr(VI) followed the pseudo-second order model with an extremely fast removal rate (the complete adsorption within 5 min). Regeneration of PDFMC could be conducted by simply washing with a mixture of NaOH and NaCl solution and the adsorbent could be used for 5 cycles of adsorption-desorption of Cr(VI) without any significant loss. The fast removal rate, applicability in a wider range of pH and easy regeneration and reusability makes the PDFMC a prospective material for magnetic separation of Cr(VI) from aquatic environments.