At present,cut-and-fill method is adopted in a growing number of mines. However, it is quite common that stopes roofs are unable to be tight by pipeline transport in filling. To tackle this problem, the paper analyzes in detail the varioud reasons to these unclosed roofs and proposes a couple of measures and methods to ensure that roofs can be tight by fill, thereby providing a new effective approach to attaining fill tightened roofs by filling and improving working conditions.