During coal mining, the fully-mechanized tunnel is always under high-concentration of dust pollution. This brings not only the potential risk of dust explosion but also makes the tunnel workers suffer from coal mine pneumoconiosis (CWP), a systemic disease featured by pulmonary fibrosis. Therefore, it is extremely important to establish a theory and optimal parameters for dust control over fullymechanized excavating tunnels. In this study, we analyzed the dust diffusion under several parameters, including the distance between the forced air opening and the cutting face (L-Y), the height of the forced air cylinder above the floor (L-H), and the distance between the center of the forced air cylinder and the nearest coal wall (L-J). The optimal dust control parameters were determined as: L-Y = 20 m, L-H = 3 m and L-J = 0.6 m. Under this condition, the airflow can effectively suppress the diffusion of dust particles. At the same time, the operating environment of the roadheader driver was remarkably improved and the requirements on miners' occupational health and safe production were satisfied. The present study proposed a new approach for occupational health of the workers in the excavating tunnel and clean production management. (C) 2020 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.