To develop a method of extracting DNA from plasmodium vivax on Giemsa:stained or unstained bloo d smears collected in different years.The malaria parasites blood smears were collected from areas of Shandong,Yunnan and Anhui provinces inrecent years.The samples of old blood smears from 1970:1990s were also invol ved in the study.An improved kit method was used for extracting DNA from Giemsa:stained or unstained blood smears.Nested PCR was employed for amplifi-cation and identification of parasite species.DNA samples were isolated from 41 Giemsa:stained or unstained blood smears which microscopy results were plasmodium vivax.Nested PCR amplification and electrophoresis results showed that malaria parasites positive rate were 71% (29/41),of which 1970:1990s old samples positive rate were 79%(11/14).Plasmodium vivax positive results had 120 bp bands,positive rate were 90%(26/29).Three samples appeared 205bp bands were identified as plasm -odium falciparum positive results.Blood smears with good quality occupied 100%(8/8) successful rate of PCR amplification,similarly,blood smears with common quality could achieved 91%(20/22) successful rate.Howev -er,blood smears with some degree of damage and loss could only occupy 10%(1/11) successful rate.It was wor -th noting that good quality Giemsa:stained blood smears without the decoloring process could occupy 100% (9 /9) successful rate of extracting DNA.Malaria parasites DNA on blood smears could be extracted successfully by using the improved kit method and had a same effect to old blood smears had been stored for thirty or forty ye -ars ago,which could achieve high positive rate of PCR amplification.Quality of blood smears was key factor to success of DNA extraction,interestingly,processing of stain or destaining almost had no effect on DNA.Furthe rmore,the method could also be used for examining the results of microscopy at the molecular level.