The Laochang Tin Mine is the mainstay of China' Tin Base Yunnan Tin Industry Corp. In the mining history several stope roof collapse disasters have occured. Roof collapses were mainly in the form of fall of loose rock, loose oxidized ore and collapse of local separating of weak intercalated layers. On the basis of stope collapse statistics of No. 14-5 orebody (major orebody of the mime) along with casualty accident which occured not long time age, according to structural characteristics of stope rockbody and roof failure characters, collapse accidents were classified. Causes and mechanism of collapse were investigated, and corresponding control measures were proposed.