Thermal analysis of laser cutting process is carried out, and the first and second law efficiencies of the cutting process are formulated. Thermal efficiencies are predicted for various laser scanning speeds and laser output power levels. The experiment is conducted to examine the resulting cutting sections. The F-test is conducted to assess the end product (cutting section) quality and, later, the thermal efficiencies are related to the end product quality. It is found that increasing laser output power lowers the first and second law efficiencies of cutting, which is more pronounced with reducing the laser scanning speeds. The end product quality improves for low laser output power levels and high laser scanning speeds similar to the thermal efficiencies. Copyright (C) 2007 John Wiley & Sons, Ltd.