Abstract: Objective: To assess the effect of the monitoring system of leprosy suspicious symptoms. Methods: The time of delayed diagnosis, misdiagnosis?rate in new cases and grade II disability incidence were assessed before and after the?implementation?of the system. Results: After implementation of the system，the time of delayed diagnosis was shortened from 36.64 to 17.86 months, the grade II disability incidence decreased from 23.15% to 12.12% and the misdiagnosis rate decreased from 23.15% to 12.12%. Conclusion：The implementation of the monitoring system of leprosy suspicious symptom can improve early diagnosis of leprosy and reduce the grade II disability.

Key words: leprosy, surveillance, effect analysis