The radical surgery required for head and neck cancer is sometimes crippling and disfiguring often forcing the patient to live a life of a recluse. Reconstructive surgery is a bridge which allows for aggressive tumor resection while maintaining a quality of life. The ideal reconstructive procedures must be reliable and be performed at the time of resection with only one stage. The use of the free flap by microvascular technique is an ideal method which satisfies the demands of reconstruction, and has been accepted rapidly in the majority of head and neck cancer centers. Since head and neck cancer treatment is one of the major problems demanding multi-disciplinary cooperation, reconstruction with free flap technique has been performed with integral team of head and neck cancer in Ajou University Hospital from September 1994. Herein, we report our analysis of cases regarding various factors in reconstruction. This report demonstrates that microvascular free tissue transfers can be done with high degree of reliability on a wide spectrum of cancer ablative surgical defects using a wide variants of flaps.