The invention discloses a tubular decorative rib, and relates to the technical field of building engineering. The tubular decorative rib comprises a tube body (1) and a connecting piece (4), wherein an open groove (101) is formed in the end part of the tube body (1); at least three radial support blocks (2) are arranged at one end of the connecting piece (4); a platy clamping block (3) is arranged at the other end of the connecting piece (4), and is provided with mounting holes for connection with a curtain wall main body; the tube body (1) is connected to the support blocks (2) in a sleeving way, and the inner cavity wall of the tube body (1) is closely attached to the end faces of the support blocks (2); the open groove (101) of the tube body is connected with the clamping block (3) in a clamping way. According to the tubular decorative rib, a connecting part is arranged in the tube body, and an inner cavity of the tube body is supported by the radial support blocks, so that the tubular decorative rib is firm in connection, and the overall attractive appearance of a curtain wall is maintained; in addition, a manner of splicing the tube body and the connecting piece is adopted for mounting, and is more convenient than a manner of fixing the connecting piece outside the tube body through a bolt.