A method of treating tunnel collapse includes leveling a collapse body and moving a pavilion support under the collapse cavity, lifting a shield plate until a lower edge of the shield plate surpasses a contour line of an initial supporting arch of a tunnel, connecting a bottom column and inserting a padding plate under a column. If the hydraulic prop retracts, the column, the bottom column, the padding plate and the hydraulic prop bear a load from the shield plate. Mounting and connecting the initial supporting arch, welding the intersection point of the column and the initial supporting arch, cutting off the column in the initial supporting arch. Transferring the load of the shield plate from the pavilion support to an initial supporting shed, spraying fast-setting concrete to a grid arch to form a closed shell, and pumping filling material to fill the space of the collapse cavity.