The invention concerns a seafloor-surface connecting installation for a submarine pipeline (10) set on the seafloor, in particular at great depth, of the hybrid-tower type comprising a static base (13-18) set on the seabed. In the inventive installation: 1) said vertical riser includes a terminal pipe portion (5.sub.1), and a flexible joint (19) which allows angular movements (.alpha.) of the upper part (5.sub.2) relative to said terminal pipe portion (5.sub.1); and 2) the terminal part (11) of said pipe resting on the seabed has a an elbow-type terminal curvature; 3) said terminal portion (5.sub.1) of the vertical riser is connected to said terminal curvature (11) by a single connecting element; and 4) said base plate (13-18) rigidly maintains in fixed vertical position and linked to each other via said connecting element (12): said terminal pipe portion (5.sub.1) and said elbow-type terminal curvature (12) the latter facing upwards.