An apparatus for predicting a body temperature is provided. The apparatus includes an external environment/activity estimation neural network configured to detect at least one facial region as a region of interest from an input thermal image of a target person to be measured, and estimate an environmental type including an external temperature and participation in physical activity based on a temperature of the at least one region of interest. The apparatus further includes a body temperature prediction neural network configured to predict a body temperature of the target person based on the environmental type estimated by the external environment/activity estimation neural network and the temperature of the at least one region of interest.
