The invention relates to a fast and fine geological orientation method for a shale gas horizontal well. Materials are collected, an orientation comparing standard well and a reference well are determined, and an orientation sign layer and a target spot predicting scheme are determined; a well zone two-dimensional geological orientation model and a well zone three-dimensional geological orientation model are built and regulated, and a two-dimensional vertical section and the three-dimensional geological orientation model of a well to be oriented are amended in time; by means of the characteristics of lithological characters, well deflection, while-drilling gamma and the like of the well to be oriented, the standard well and the reference well, stratum comparing is conducted; the position where a drill is located is judged through three figures, one table and the like; whether the position where the drill is located is in a high-quality shale gas layer section or not is evaluated while drilling; whether an initial geological model is applicable or not is judged; through an equal-thickness comparing method a target spot A is determined and regulated, a target spot B is predicted, and a track of a borehole in a horizontal section is controlled; and the pass-through rate of a high-quality shale gas layer is calculated according to the statistic drilling-meeting thicknesses of a shale reservoir and a high-quality shale reservoir, whether the track is controlled to reach the target spot B or not is judged, and the fast geological orientation effect is evaluated. Fast orientation is achieved, the application range is wide, and application and popularization are easy.