There are many ways of nitrogen transformation in wastewater treatment, among which dissimilatory nitrate reduction to ammonium (DNRA) convert NO₃^-/NO₂^- into NH₄⁺, which is an important part of nitrogen transformation.This paper reviews the two-step reaction mechanism of DNRA process and microorganisms involved. In addition, the potential factors affecting the DNRA process in wastewater treatment, such as dissolved oxygen, types of carbon or nitrogen sources, C/N ratio, temperature, pH and special substances contained in wastewater,are emphatically discussed to explore how to regulate the competition between DNRA and denitrification fornitrate, and this paper introduces two main analytical methods for DNRA process in wastewater treatment.This paper confirms the occurrence and contribution of DNRA process in wastewater treatment, and the in-depth study of DNRA is of great significance for the removal or recovery of nitrogen in wastewater.