Interleukin-2 (IL-2) is used as a therapeutic agent in the treatment of cancer and autoimmune diseases. However, in Vietnam, the price of IL-2 used for in vitro experiments is expensive. Objectives: This study aims to express recombinant human IL-2 fused with SUMO in Escherichia coli. Methods: Plasmid pET-SUMO-il2 was transformed into E. coli BL21(DE3) for the expression of IL-2 with SUMO tag. Expression conditions for optimal soluble recombinant IL-2 were examined, including culture medium (LB, TB, ZYP-5052); IPTG concentration (0.02, 0.1, and 0.5 mM); culture temperature (25°C and 37℃). The recombinant IL-2 fused with SUMO tag was purified by immobilized metal affinity chromatography method (IMAC). Results: The transformed bacteria can express SUMO-IL-2 with high yield in TB medium induced by 0.1 mM IPTG at 25°C. From 200 mL of bacterial culture, we obtained approximately 108 mg of purified protein by IMAC. Conclusions: In this study, we have successfully transformed E. coli BL21(DE3) with the recombinant plasmid pET-SUMO-il2. The bacteria could express soluble SUMO-IL-2 with high yield and the pure protein was obtained by 1-step purification using Ni Sepharose column.