Osteopontin, a glycoprotein, is expressed in several tissues including the mammary gland. The gene has been reported to be associated with milk and its constituents in various livestock species. This gene was sequenced in buffalo and it coded for the protein of 280 amino acids with the conserved GRGDS domain. The sequence was confirmed from the cDNA sequence derived from the mammary gland of buffalo. The earlier-reported 9T/10T variation in the upstream region of the gene was investigated for its effect on milk in buffalo and it was found to be non-significant.