Abstract: For easy access to flotation tailings image information and defining the image grayscale in relation to ash of tailings,an investigation is made into the feasibility of developing a flotation tailings image sampling analysis system using the USB video acquisition card coupled with VS2010 platform,based on Open CV open-source computer vision function library. The system can collect the images if tailings at preset time interval and then convert the images into gray images using Open CV’s self-built video function library. Finally,the images and gray images are sorted after eliminating the interference of light and air bubbles during the sampling process with software algorithm. Result of study indicates the system can collect image with noticeably improved objectivity and authenticity. This provides a coat-effective and high-performance reliable approach for verifying the relationship between grayscale of image and ash of tailings.