To obtain a copper alloy useful as a heat radiation material used in contact with a material of low thermal expansion coefficient, such as resin mold, by incorporating, as a secondary phase of specific aspect ratio, specific amounts of phase-separation- type Cr, Mo, W, Nb, etc. into Cu as a base phase of a copper alloy.

Cr, Mo, W, Nb, etc. are incorporated as a secondary phase having an aspect ratio of ≥10, desirably about ≥100, into a copper alloy containing 2-50 wt.%, in total, of at least one element among Cr, Mo, W, and Nb. The copper alloy can be obtained by adding prescribed amounts of at least one element among Cr, Mo, W, and Nb to pure copper of oxygen-free copper to be a base phase, melting the mixture, casting the resultant molten alloy, hot-working the resultant ingot, and further applying cold working such as flat roll rolling at about ≤300°C. By this method, the copper alloy with low expansion coefficient and high thermal conductivity can be obtained. The copper alloy can be suitably used as heat radiation material for electrical and electronic equipment parts, and has no possibility of causing, due to difference in thermal expansion, breakage to a resin mold, etc. in contact with the copper alloy itself.