In order to monitor the dust concentration of particle materials in the process of handling and transportation online in real time and improve the accuracy and reliability of dust concentration measurement results, an improved dust concentration measurement algorithm based on the eigenvalue calculation of image transmittance was proposed. First, the experimental platform of vision measurement of dust concentration was established, and the dust images were collected. Then, the characteristics of transmittance of dust images were extracted. Based on the dark channel theory, the image transmittance of dust images was calculated by combining the information of image saturation and image brightness. Finally, the mapping relationship between dust concentration and image transmittance was established by the polynomial fitting method. And the high-efficiency and high-precision measurement of dust concentration was realized. The research results show that the proposed algorithm can not only effectively measure the dust concentration, but also the average relative error is only 7.77%. The accuracy is effectively improved and the measurement range is further expanded.