Diamond was deposited on copper (Cu) substrates in open atmosphere using a C2H2/O2 combustion flame. Graphite powders were used as seeds. The graphiteseeded Cu substrates were heated by a CW CO 2 laser to about 750 °C within 1 min at the initial stages of deposition. It was found that diamond nucleation density after graphite seeding and laser irradiation was more than three times as much as that on the virgin Cu substrates. As a consequence, diamond films up to 4 μm were obtained in 5 min. The enhancement of diamond nucleation was attributed to the formation of defects and edges during the etching of the seeding graphite layers by the OH radicals in the flame. The defects and edges served as nucleation sites for diamond formation. The function of the CO2 laser was to rapidly heat the deposition areas to create a favorable temperature for diamond nucleation and growth. Scanning electron microscopy (SEM) and Raman spectroscopy were used to characterize the deposited diamond films. A mechanism for diamond nucleation and growth on Cu substrates with graphite seeding was proposed.