An infrared ray-tracing lens module is provided. The infrared ray-tracing lens module is adapted to receive light from an object. The infrared ray-tracing lens module includes a first positive diopter lens, a second positive diopter lens, a negative diopter lens and an image unit. The first positive diopter lens, the second positive diopter lens and the negative diopter lens are arranged along an optical axis, and the light travels from the object, sequentially passes through the first positive diopter lens, the second positive diopter lens and the negative diopter lens to be projected to the image unit.