In　this　article,　a　new　kind　of　hairpin　DNA　Electrochemical　biosensor　using　nitroacridone　as　electrochemical　indicator　was　first　designed,　and　used　to　detect　BCR/ABL　fusion　gene　in　Chronic　Myelogenous　Leukemia　(CML).　The　results　indicated　that　in　pH　7.0　Tris-HCl　buffer　solution,　the　oxidation　peak　current　was　linear　with　the　concentration　of　complementary　strand　in　the　range　of　6.2　x　10(-8)-3.1　x　10(-7)　mol/l　with　a　detection　limit　of　5.3　x　10(-9)　mol/l.　This　new　hairpin　DNA　electrochemical　biosensor　demonstrates　its　excellent　specificity　for　single-base　mismatch　and　complementary　(dsDNA)　after　hybridization,　and　this　probe　has　been　used　for　assay　of　PCR　product　of　a　real　sample　with　satisfactory　result.　(c)　2008　Elsevier　B.V.　All　rights　reserved.