Abstract: An infrared temperature sensing device with projecting function is using for sensing temperature of a measured body. The infrared temperature sensing device includes a temperature-sensing element, a Fresnel lens, a microprocessor and a projecting module. The temperature-sensing element is used for sensing infrared radiation and deriving at least a temperature signal. The Fresnel lens is located between the measured body and the temperature-sensing element for focusing the infrared radiation on the temperature-sensing element. The microprocessor is electrically connected to the temperature-sensing element. The projecting module is electrically connected to the microprocessor and projecting at least a body temperature value corresponding to the temperature signal.