Abstract: The roof abscission layer is one of the main forms of roadway surrounding rock deformation and damage, when it exceeds a certain limit, the roof is in an unstable situation and will very easily result in accidents. The roof separation indicator is an instrument that can effectively monitor roof movement. Based on the measuring principle of roof abscission layer and practice experience, the design idea of soft-contact roof separation indicator with fixed airbag which connect with micro-deformation hose is put forward creatively, a new idea that compensating the shortage and developing the roof separation indicator is provided.