Interleukin 2 is a key immunoregulatory cytokine that is involved in T helper differentiation and is known to induce interferon gamma (IFN-gamma) in natural killer (NK) and T-cell. The gene for interleukin-2 (IL-2) was amplified from cDNA pool prepared from ConAstimulated peripheral blood mononuclear cells (PBM cells) isolated from Nilgai reared in semicaptivity. The amplified IL-2 gene was cloned and nucleotide sequences were determined. The sequencing result showed that Nilgai IL-2 cDNA contains 468 bp long ORF encoding 155 amino acids (Genbank Accession No DQ017831). Homology comparison of nucleotide revealed that Nilgai IL-2 sequence is evolutionary more related to buffalo than cattle IL-2 sequence.