Abstract: Objective To explorea smiple and effective method for the extraction of Mycobacter iumtuberculosis DNA from paraff in embedded tissue.Methods The Mycobacter iumtuberculosis DNA was extracted from 20 specmiens of 4% formalin fixed,paraffin-embedded lung or lymphnodetissues using salting-out procedure,phenol chloro form method,one step method,and genomic DNA purification kit.The quality of DNA was analyzed by agarose gelelectrophoresis,polymer asecha in reaction(PCR),and genemem brane chip.Results Salting out procedure and one step methodyielded more DNA.However,the value of A₂₆₀/A₂₈₀ of DNA extracted by one step method was lower than that of the other three methods.Genomic DNA was obtained by all methods through electropho resis.PCR and genemem brane chiptests showed that the Mycobac teriumtuber culosis DNA was detected in the DNA extracted by all methods except one step method.Conclusion The salting out procedure for extraction of Mycobac teriumtuberculosis DNA from paraffin-embedded tissue is more efficient and simple.