This study was aimed to investigate the expression characteristics of HSP70 protein/mRNA, pim-1 mRNA in bone marrow mononuclear cells from leukemia patients, and to clarify whether these changes are related to leukemia type, tumor burden of leukemia, therapeutic reaction and prognosis. HSP70 mRNA and pim-1 mRNA in BMMNCs were detected with semi-quantitative RT-PCR in 40 leukemia patients and 10 controls. HSP70 protein in BMMNCs was assayed with Western blot in 34 leukemia patients and 10 controls. Relation of HSP70 and pim-1 expression with leukemia classification, the degree of tumor burden and therapeutic reaction were analyzed. The results showed that the BMMNCs from both leukemia patients and controls expressed HSP70 protein/mRNA. The mean ODR value of HSP70 mRNA in BMMNCs from leukemia patients was significantly higher than that of the controls; the mean ODR value of HSP70 protein/mRNA in acute myeloid leukemia and chronic myeloid leukemia patients both were significantly higher than that of acute lymphocytic leukemia patients; the mean ODR value of HSP70 protein/mRNA in acute leukemia patients with high-degree tumor burden was higher than that of the patients with low-degree tumor burden; the mean ODR value of HSP70 protein/mRNA in the patients after chemotherapy was significantly higher than that of the patients before chemotherapy; the BMMNCs from both leukemia patients and controls expressed pim-1 mRNA. The mean ODR value of pim-1 mRNA in BMMNCs from leukemia patients was significantly higher than that of the controls; the mean ODR value of pim-1 mRNA in BMMNCs for Acute lymphocytic leukemia patients was significantly higher than that of the patients suffered from acute myeloid leukemia and chronic granulocytic leukemia; there was a positive relationship between pim-1 mRNA and HSP70 mRNA expressions in leukemia patients (p < 0.05). It is concluded that there are high expressions of HSP70 and pim-1 in leukemia and their positive correlation is shown. The over-expressions of HSP70 and pim-1 protein/mRNA are related to tumor burden in leukemia patients.