This paper summarized the outstanding achievements of Yankuang on the areas of long wall top coal caving technology (LTCC). Analysis and research have been done through site tests on the characteristics of dynamic movement of supports at coal face, the caving breakage, power transmission regulations and the existing problems in four leg low level shield supports. The paper recommends a new type support, which can further improve the relationship between supports and wall rock, and also prospects the future development of LTCC technology.