Infrared extinction ability and application of tiny graphite powder in combustible antiinfrared smoke screen were studied. Results show that infrared extinction ability of dispersed graphite is stronger when its granularity is smaller. The graphite can burn when it is used in combustible antiinfrared smoke screen. When graphite is added from 20% to 5% respectively,its burning loss is accordingly increased from 31.6% to 57.6% in formula containing organic combustible and from 44.6% to 80.5% in formula containing metal combustible. In order to make use of graphite effectively,5% carbon black is added into combustible antiinfrared aerosol containing oxidant,organic combustible and 20% graphite. Compared to the original formula,the use of carbon black can effectively prevent combustion of graphite and improve infrared extinction of smoke screen containing graphite.