The low efficiency of excavation and support in coal roadway is common. The unreasonable selection of excavation and support construction parameters increases the risk of heading and roof fall, which seriously affects the production efficiency. In order to solve the problem of safety and high efficiency in the process of coal roadway excavation, using theoretical analysis, numerical simulation and field test methods, combined with the geological conditions of the north wing ( 2-2052 roadway ) of Hejin Tenghui Coal Industry, the physical and mechanical model of the roof in the unsupported roof area was established by using the thin plate theory. FLAC three-dimensional numerical simulation was used to simulate the influence of factors such as unsupported roof distance, roadway width and roof support strength on the stability of the roof in the unsupported roof area, and the mine pressure appearance law and deformation characteristics of the roof in the head-on unsupported roof area of coal roadway excavation were systematically studied. The results show that the roof of the unsupported roof area is destroyed under the combined action of tension and shear. Numerical simulation is used to simulate the vertical stress of roof surrounding rock with different head-on distances ( 2,4,6,8m ) in front of the lagging support section, and considering the safety factor of the unsupported roof area, it is concluded that the limit unsupported roof distance is 4m.During the test period, the maximum settlement deformation of the roof is 62 mm, and the roof of the unsupported roof area of the heading head has not occurred. The roof stability is excellent and meets the production requirements during the whole service period.