Abstract: A hot working material of corrosion resistant copper-based alloy having a metal composition of 61.0 weight percent to less than 63.0 weight percent copper, 1.0 weight percent to 3.5 weight percent lead, 0.7 weight percent to 1.2 weight percent tin, 0.2 weight percent to 0.7 weight percent nickel, 0.03 weight percent to 0.4 weight percent iron, 0.02 weight percent to 0.10 weight percent antimony, and 0.04 weight percent to 0.15 weight percent phosphorus, with the balance composed of zinc and inevitable accompanying impurities. The alloy is subjected to hot working and subsequent heat treatment at 500.degree. C. to 600.degree. C. for 30 minutes to 3 hours and sufficient that the alloy has an .alpha. single-phase structure and addition elements are dispersed uniformly in the entire structure.