Abstract: Objective To discuss a new model of Quality control (QC) system for sputum smear microscopic examination laboratory in tuberculosis.Methods The sputum smears of newly registered tuberculosis patients were key points of QC system.To carry out elementary QC with double blind in district (county) class sputum smear microscopic examination laboratory .The province class reference laboratory was set for final QC exam.Results In keeping current cost,local QC rate could reach to 100%,about 50% sputum smears of newly registered tuberculosis patients were supervised under QC system every year.The positive detection rate was decreased from 99.0%～100% to 97.1%～98.3%,and the negative detection rate was decreased from 99.4%～99.9% to 98.5～99.1%.Conclusion Using double blind to carry out QC in equal class examination laboratory is an economical supervise method.It can spread QC scope and QC frequency efficiently.Two different class examiniation laboratory mate the QC process more strictly,which can play an important role in tuberclosis programe.

Key words: M.tuberculosis, Quality Control, Sputum, Microscopic