As the cemented filling with rod milling tailings has been changed into one with waste rock and mortar in Tongkeng tin mine,the orepass situated in the subsidence area must be used.In this case,the problems on orepass blockage,debris flow out of orepass,slime depositing and hardening under the electric vibrating platform,repair of cone installation and so on are unfavourable to the waste rock filling.According to his experience in practice,the author makes and approach to these problems,and puts forward some special viewpoints on solving them.