A copper alloy, containing: Ni and/or Si, and at least one or more of B, Al, As, Hf, Zr, Cr, Ti, C, Fe, P, In, Sb, Mn, Ta, V, S, O, N, Misch metal (MM), Co, and Be, with a balance being Cu and inevitable impurities; the copper alloy having a precipitate X composed of Ni and Si; and a precipitate Y composed of Ni and/or Si, and at least one or more of B, Al, As, Hf, Zr, Cr, Ti, C, Fe, P, In, Sb, Mn, Ta, V, S, O, N, Misch metal (MM), Co, and Be, in which a grain diameter of the precipitate Y is 0.01 to 2 μm.