From April 1985 to March 1986 there were 48 cases of laser breast operations. Twelve cases of breast cancer were treated by modified radical mastectomy using a CO2 laser. Another twelve cases of breast cancer were treated conventionally using a scalped and electrocautery for the purpose of comparison. Laser surgery offers some advantages. The conventional surgery involved more blood loss (300 ml to 750 ml) and needed blood transfusion, whereas laser surgery produced a 200 ml to 400 ml blood loss with no need for transfusion. Since in laser surgery, cutting and ligation is by sealing, the laser operations took a shorter time, from 1.5 hours to 3 hours, whereas conventional surgery took 2 hours to 3.5 hours. All of the 24 cases of breast cancer, treated either by conventional or by laser surgery, had stitches removed on the tenth day. No wound disruption was observed in either group. In conclusion, laser surgery can provide a very safe and effective method in the treatment of breast cancer.