Based on the research status of moving bed biofilm reactor (MBBR), the characteristics and reaction mechanisms of the anammox process were discussed. The effects of matrix concentrations, organic matter, temperature, dissolved oxygen and other factors on the stability of the process were analyzed. The application of MBBR was prospected with engineering cases. The analysis showed that a low concentration of COD and an appropriate NH+4 -N/NO-2 -N ratio were conducive to the anammox process. It was necessary to maintain the activity of low-temperature anaerobic ammonia oxidation bacteria (AAOB) in the practical application. Precise control of DO and the fluidization state of the filler could promote the enrichment of AAOB on the MBBR biofilm, which promoted the stable denitrification effect of anammox process.