In order to extract the effect characteristic parameters （smoke screen width， smoke screen height， smoke screen coverage area， masking time） and motion characteristic parameters （vertical and horizontal diffusion speed） from measured infrared smoke screens and， the layout of the test site for field measurement of infrared smoke screens was designed. The infrared thermal imager was used to collect the video data of the explosion and diffusion process of the infrared smoke bomb in 112 secs， and the five-frame difference method was used to segment and extract the infrared smoke screen from the video sequence of the infrared thermal imager， then the effect characteristic parameter area and motion characteristic parameter area of the infrared smoke screen were obtained. According to the geometric relationship of the site layout， the test results have been corrected for wind direction. The pixel points of the infrared smoke screen image were used as the basic unit that the actual smoke screen height and width values represented by each pixel in each frame of the video sequence were solved， and then the effect characteristic parameters and motion characteristic parameters of the infrared smoke screen were obtained. It was verified by the analysis of actually measured infrared smoke screen videos that this method can quickly extract the characteristic parameters of infrared smoke screen. At the moment of explosion， the width， height， and area of the smoke screen rapidly increase to 4.7 m， 5.2 m， and 24.2 m²， respectively， and the front diffusion speeds along the wind direction reached 126 m∙s^-1 horizontally and 146.3 m∙s^-1 vertically.， It has highly practical application value for the research on infrared smoke screens， including the correction of diffusion simulation equation， the combat effectiveness evaluation， and on the combat operation.