Laser surface alloying of commercially pure copper (cp Cu) with preplaced Ti powder has been successfully achieved using a high power diode laser. All laser-alloyed specimens have corrosion potentials in between that of cp Cu and commercially pure titanium (cp Ti) and their corrosion current densities are lower than that of cp Cu. Particularly, the specimen with 85. wt.% Ti fabricated at scanning speed of 35. mm/s shows the highest corrosion resistance, that is, about 150 times that of cp Cu and very close to that of cp Ti. Improvement of corrosion resistance is attributed to presence of Ti in the intermetallic and metallic phases for forming the protective oxide.