Abstract: Objective: To explore an effective method for extraction and PCR amplification of mitochondrial DNA from paraffin-embedded lymphoma tissue.Methods: Twenty seven paraffin-embedded lymphoma tissue specimens were selected.The two methods:Xylene/ethanol method and 0.5% Tween-20 method were used for deparaffinisation.The component and concentration of lysis buffer were modified,and mitochondrial DNA was extracted by phend and chloroform.The obtained mitochondrial DNA was analyzed by PCR amplification.Results: The DNA purity and concentration which extracted by 0.5% Tween-20 deparaffinisation method was obviously higher than that by Xylene/ethanol deparaffinisation method.The successrate of PCR amplification was 11.1% by Xylene/ethanol method and 40.7% by 0.5% Tween-20 method,respectively.There was significant statistical difference (P<0.05).Conclusions: Both the Xylene/ethanol deparaffinisation method and 0.5% Tween-20 deparaffinisation method can extract mitochondrial DNA.But the 0.5% Tween-20 method is simple,the success rate is high,and can reduce the contact chance from poisonous chemical reagents such as dimethylbenzene.So the 0.5% Tween-20 deparaffinisation method is an ideal method for extraction of mitochondrial DNA from paraffin-embedded tissues.