The invention belongs to the technical field of dredging equipment, and discloses a clogging-preventing riverway dredging system. The clogging-preventing riverway dredging system comprises a carrier, a suction structure, a clogging-preventing structure and a mud storage structure, wherein the suction structure, the clogging-preventing structure and the mud storage structure are arranged on the carrier; the suction structure is connected with the mud storage structure through the clogging-preventing structure; the clogging-preventing structure comprises a filtering cylinder, a filtering screen, a fixed support and a sealing cover; the fixed support is fixed into the filtering cylinder, and the filtering screen is arranged on the fixed support; the sealing cover is fixed to the filtering cylinder; a liquid inlet is formed in the position, above the filtering screen, of the upper portion of the filtering cylinder and is connected with the suction structure; and a liquid outlet is formed in the position, below the filtering screen, of the lower portion of the filtering cylinder and is connected with the mud storage structure. The clogging-preventing riverway dredging system is convenient to operate and transport and high in dredging effect.