Abstract: The support designs of coal roadways ought to be targeted, because their use and service time are all different in Wongawilli mining area. Rules of roadway deformation was analyzed by mechanical models and numerical models. Based on the theory of rock beam, the mechanical model of roof was founded. These parameters, thickness of rock beam, width of roadway and allowable tensile stress of roof, meet with hyperbolic curve. Combined with FLAC3D, four kinds of support were analyzed. By analyzing support effect to surrounding rock and bolts, the corners and sides of roadway are determined to be key positions of roadway support. According to data of rock deformation, sides support is better than roof support only. FRP bolts can be used for sides support in branch roadway. The effect of bolts parameters to rock deformation were studied, the results show that strengthening sides support is useful to stability of roof rock, and there is a optimum value to length of side-bolts.