Provided is a copper-manganese-nickel based alloy having characteristics (in particular, specific resistance) close to those of a nickel-chromium based alloy. It is also an objective to provide an alloy having high processability compared to a nickel-chromium based alloy. An alloy for a resistive body includes copper, manganese, and nickel, wherein the manganese is 33 to 38% by mass, and the nickel is 8 to 15% by mass.