Acute promyelocytic leukemia is classified with a classic translocation  t(15;17) (q22;q12), and the other subtypes such as: t(11;17 ( (q23;q21) , t(11;17)) q13;q21)  t(5;17) (q35;q21).   Unfortunately, about 5% of APL subtypes, do not have a good prognosis due to resistance to ATRA.   Therefore, there is a major concern for hematologists and oncologists to diagnosis subtype of APL and start the treatments as soon as possible. 28 patients with suspected acute promyelocytic leukemia who hospitalized in two Iranian general hospitals were under study . In this study, we applied molecular and western blotting methods to detect major oncoproteins in APL subtypes. Cytogenetic results have been shown that the PML / RARa oncogene is positive in 26 of patients, and two of them did not have appreciated result. The results of western blotting showed that in 26 patients, the proteins with molecular weights 115 and 85 KD was detected by specific anti-RARa antibodies. The western blotting assay for one patient showed the protein with molecular weight of 85 KD was detected by specific anti- PLZF antibodies. The results indicate that the molecular and western blotting techniques were able to differentiate the APL with t (15; 17) from the other subtypes, like t (11; 17). We indicated by western blotting, two oncoproteins:  PML / RARa and PLZF / RARa, respectively to the relative two translocation t (15; 17) and t (11; 17). Western blotting techniques can be a substantial contribution of to the final diagnosis of leukemia.