A Cu—Ga binary alloy sputtering target having excellent mechanical workability, high density, and high bending strength, and a method of producing the sputtering target are provided. The sputtering target has a composition including 28 to 35 atomic % of Ga and the balance made of Cu and inevitable impurities. In addition, the sputtering target has a coexistence microstructure in which a low-Ga-containing Cu—Ga binary alloy phase is surrounded by a high-Ga-containing Cu—Ga binary alloy phase. The low-Ga-containing Cu—Ga binary alloy phase includes 26 atomic % or less of Ga and a balance made of Cu. The high-Ga-containing Cu—Ga binary alloy phase includes 28 atomic % or more of Ga.