Disclosed is a filtering apparatus capable of minimizing the relative vibration of the filtering membrane module within the frame structure during the aeration cleaning process, thereby preventing the damage of the filtering membrane module which might be caused due to the relative vibration as well as the separation of the filtering membrane module from the frame structure. The filtering apparatus comprises a frame structure including a cross bar and a filtering membrane module installed in the frame structure. The cross bar comprises a first rib inserted into a receiver of the header of the filtering membrane module. The filtering apparatus further comprises a stopper fastened to an end of the first rib passing through a through-hole of the receiver so as to prevent the filtering membrane module from being separated from the frame structure.