Freeze-thaw cycles are key drivers of soil nitrogen (N)cycling in cold ecosystems. Studies have shown that freeze-thaw cycles can enhance N turnover and alleviate N-limitation of plant growth due to the deficiency of soil-available N. However,loss of N is prevailing as a result of available N oversupply during freeze-thaw period. The extra available N mainly losses occurring through N_2O emission, leaching and runoff. Here,we summarized the observational and experimental evidence to assess (1)the impact of freeze-thaw cycles on N loss,(2)the environmental factors and mechanisms influencing N_2O emission during the process of freeze-thaw cycles,(3)the relationships between N loss and N availability (N mineralization,dissolved organic N,and microbial biomass N),and (4)the shortcomings in current research. We suggest that the main focus of research in the near future will be related to effects on N loss and availability of freeze-thaw cycles,for use in modeling,soil microbial function,mediators of N transformation,and plant-soil interactions.