Abstract: Based on the battlefield environment for performing operational mission, emphasis should be placed on the threat from infrared guided missile when conducting infrared stealth for armed helicopter. Modes and developing tendency of infrared guidance were introduced, calculation formulas of performance range of point-source and imaging guided missile were derived, and two approaches, theoretical analysis computation and flight measurement, of obtaining infrared radiation characteristic of armed helicopter were described. Effects of radiation intensity and difference in temperature on missile performance range were studied through samples. Infrared suppression effects and approaches were analyzed.