In this study, porous ceramsite carrier was modified using magnetic material as raw material. The magnetic porous ceramsite carrier was applied to the treatment of municipal landfill leachate. The results showed that the removal efficiency of chemical oxygen demand (COD), NH3-N and Cr6+ in the supernatant were all more than 90% after 30 days with the aeration rate of 3 L/h, the aeration time of 16 h/d and the temperature of 20–30 °C. The output concentration met the national life Landfill Pollution Control Standard (PR China GB16889-2008) requirements. The magnetic properties significantly improved the carrier biofilm formation, compared with the conventional activated sludge process and non-magnetic carrier. The COD, NH3-N and Cr6+ removal efficiency were 5–10%, 5–7% and 5–10%, respectively.