Transcutaneous oxygen tension measurement was studied at different degrees of temperature 37oc 40oc and 45oc in thirteen healthy subjects. TcPo2 values were taken at nine different locations on right side of the body . The effect of age , sex , height , weight , surface area , body mass index and hemoglobin level on TcPo2 Values were studied at different temperatures . The results were discussed , and we concluded that measurement of TcPo2 at 45o c appears the most reliable method for measurement of TcPo2 .The effect of different physiological variables were least affecting at supraorbital, submandibular , foot , leg and therefore these sites can be used for routine measurements of TcPo2 in clinical situations