With the improvement of the living standard, people pay more and more attention to self-health. Body temperature is an important indicator of health. Detection of this physiological index is the first step for self-assessment of health condition. Therefore, the rmometer occupies a very important position in the medical field. It brings great convenience for people s life. The traditional mercury thermometer has two shortcomings. First, using the traditional mercury thermometer costs a longer time to measure. Second, if disinfection of mercury thermometer is not completely, it may lead to cross infection. Also the electronic thermometer using thermistors may have a larger error for measurement. Measurement of body temperature in safety and accuracy is very necessary when SARS and all kinds of flu break out in the airport, railway stations, schools and other crowded place. Therefore, it makes sense to research contactless smart thermometer.-Thermometer design based on MLX90614