OBJECTIVE: In this study, we tested the correlation between the body temperature measured by non-contact temporal artery thermometer which has been developed recently and the rectal temperature using conventional glass mercury thermometer, also evaluate the reliability of non-contact temporal artery thermometer by comparing with other methods of temperature measurement. METHODS: One-hundred-and-seventeen newborn infants who were born at Samsung Cheil Hospital were included in this study. Tympanic and forehead temperatures were taken three times each with tympanic thermometer and non-contact infrared temporal artery thermometer respectively on a newborn infant by two authors. we also measured the rectal and axillary temperatures by using a mercury-in-glass thermometer. RESULTS: The normal body temperature measured by non-contact temporal artery thermometer was 36.2 +/- 0.22degrees C, and rectal, axillary and tympanic temperatures were 36.8 +/- 0.30degrees C, 36.7 +/- 0.30 and 36.1 +/- 0.27degrees C, respectively. There was a significant correlation between temperatures measured by non-contact temporal artery thermometer and rectal temperature (p<0.01, r=0.891). The differences between repeated measurements by non-contact temporal artery thermometer were significantly less than those by tympanic thermometer (p<0.01). CONCLUSION: Forehead temperature measured by non-contact temporal artery thermometer is correlated with rectal temperature and has good reproducibility. It can be used to measure body temperature in newborn infants.