The invention provides an infrared imaging system. The infrared imaging system comprises a first far infrared polarized light generating device, a second far infrared polarized light generating device, a signal receiving device and a computer; the first far infrared polarized light generating device comprises a first far infrared light source, a first polarization device, a first heating device heating the first polarization device, and a first polarization analyzer which is the same as the first polarization device in polarization direction; the second far infrared polarized light generatingdevice comprises a second far infrared light source, a second polarization device which is perpendicular to the first polarization device in polarization direction, a second heating device heating thesecond polarization device, and a second polarization analyzer which is the same as the second polarization device in polarization direction; the signal receiving device comprises a first signal receiver and a second signal receiver; and the computer which is electrically connected with the first signal receiver and the second signal receiver to integrate signals received by the first signal receiver with signals received by the second signal receiver.