The aim of this study was to investigate bag3 gene expression in chronic lymphocytic leukemia (CLL)patients and its association with clinical prognosis. A total of 46 blood samples from untreated CLL patients were collected, SYBR Green-based real-time PCR was used to detect the bag3 mRNA expression, and its association with prognostic index was analyzed by statistical software. The results showed that the median values of bag3 level detected by real-time PCR in 46 CLL patients and normal controls were 0.021 (0.0007 - 1.124) and 0.0025 (0.0005 - 0.014) respectively, the former was significantly higher than the latter. The bag3 level in drug-resistant group was obviously higher as compared with the drug-responsive group. No association was found between bag3 expression and patient clinical baseline information (gender and age) as well as established prognostic factors (lymphocyte count, disease stage, IgVH mutation status, cytogenetics analysis and CD38, ZAP 70 expression). It is concluded that the bag3 expression in CLL patients is markedly higher than that in normal controls, while the high bag3 level in CML patients is probably related with drug resistance, but is not related with clinically established prognostic factors.