Abstract: The integrated partial nitritation anaerobic ammonia oxidation (PN/A) technology is gaining significant traction in nitrogen-containing wastewater treatment due to its cost-effectiveness, small footprint, and minimal sludge production. Therefore, this review presents a thorough examination of the principles, current applications, and predominant challenges encountered in the integrated PN/A process. An analysis was conducted on challenges hindering the engineering application of anaerobic ammonia-oxidizing bacteria (AnAOB), including slow growth, sludge loss, and difficulty in suppressing nitrite-oxidizing bacteria (NOB). Corresponding strategies for resolution were proposed. Enhancing the engineering implementation of integrated PN/A for low-ammonia nitrogen wastewater treatment, establishing stable operation strategies for PN/A under low-temperature conditions, effective enrichment of AnAOB, developing protective carriers, and implementing a sophisticated automated control system by integrating pivotal factors for process enhancement constitute the future research priorities for integrated PN/A.