An experimental study on the in situ explosive fragmentation and leaching of a separate orebody,which was uneconomical value to the conventional mining,was made on a 10000t scale in NO.745 Mine.In the test,the heaps were constructed by the longhole blasting.In order to control the heap shape and the ore grain size,the method and parameters of longhole caving were analyzed.According to the practical conditions of mining technology for the test orebody,the suitable stope bottom structure was selected to hit the targets of both multi point solution containment and preventing the leaching solution leakage.