Abstract: The combined model of open-pit with underground mine has always been adopted by metal mine and inclined coal seam mine before, and we used the method of open-pit or underground mining to mine the shallow horizontal thick coal seam previously. Recent years, in China's major coal production base Pingshuo mining area, the method of combining caving mine and open-pit method was adopted to exploit the shallow horizontal thick coal seam, and it has already made considerable economic benefits. In this paper, the influence of adopting caving mining method in shallow horizontal thick coal seam to open-pit mining and slope stability is analyzed detailedly, the open questions and research technique are also put forward.