The aim of this study is to detect the biologic and/or prognostic significance of survivin (S) and effector protease receptor 1: EPR-1 (E) expression in acute leukemias (34 ALL and 40 AML) by using RT-PCR. S and E expressions were found in 83.8 and 20.3% of the cases, respectively. S was detected in 90%, 76.5% and E was detected in 17.5%, 23.5% of the cases with AML and ALL, respectively. There was a significant correlation between S and E (r=0.30 p=0.01). Mortality rate was higher in E(-) cases than E(+) cases (83.1 % versus 66.7%) (p=0.04). The median DFS and OS rates were shorter in S(+) and E(-) cases. In subgroup analysis, there was not a significant difference for OS between S(-) and S(+) cases and E(-) and E(+) cases in ALL group. The median OS rate was significantly longer in S(-) cases than S(+) cases, and longer in E(+) cases than E(-) in AML groups (p=0.04, 0.001, respectively). OS and DFS rates were longest in S(-) E(+) cases and shortest in S(+) E(-) cases (p=0.04 and 0.03, respectively). In multivariate analyses EPR1 negativity was found to be an independent poor risk factor for survival (OR: 2.4, p=0.02).