Provided is a Co-based alloy for a living body based on Co—Cr—W—Fe, including a composition of Cr: 5% by mass to 30% by mass, W: 5% by mass to 20% by mass, Fe: 1% by mass to 15% by mass, Co as the remainder, and unavoidable impurities. In this alloy, when the content of W is 5% by mass to 10% by mass, the content of Fe can be set to be in a range of 1% by mass to 5% by mass, and when the content of W is 11% by mass to 20% by mass, the content of Fe can be set to be in a range of 3% by mass to 15% by mass.
