A strain of microorganism that demonstrated efficient nitrogen removal potential under low C/N conditions was screened from landfill leachate. The strain was identified as Galactomyces candidum by ITS sequencing, and growth density and removal of ammonia nitrogen were assessed after 24 h of incubation. The results showed that the optimum ammonia nitrogen reduction conditions for G. candidum was at pH 8.0 and 30 ℃, with a C/N ratio of 1.5; the highest rate of ammonia nitrogen removal was 93.1%. This novel function of G. candidum offers great potential in the removal of ammonia nitrogen from sewage, especially in low C/N wastewater. Our study provides a new theoretical basis for the industrial application of microorganism in the biochemical treatment of wastewater and reduces environmental pollution.