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Based on the testing example of visibility measurement and testing laboratory (Hefei), the measurement uncertainty evaluation method of visibility measurement and testing results with a forward scattering visibility meter are presented. Firstly, the composition and technical requirements of the visibility detection system are introduced. Secondly, the measurement model of the indication error of the forward scattering visibility meter is established, and the source of measurement uncertainty is analyzed. Finally, the measurement uncertainty component is evaluated according to different evaluation methods. The results show that the uncertainty components of the forward scattering visibility meter mainly include the visibility meter to be measured, the measuring standard and the standard uncertainty introduced by the test chamber. At 50 m and 200 m detection points, the indication error’s extended uncertainty U (k=2) is 4.9 m and 14.3 m, respectively. The relative extended uncertainty U (k=2) is between 8.5% and 11.0% at the detection point from 500 m to 10,000 m.