The utility model discloses a marine riser suspension device. The marine riser suspension device comprises a suspension short section; the suspension short section comprises a middle section and transition sections arranged at the two ends of the middle section, and the wall thickness of the transition sections is smaller than that of the middle section. A centralizer is arranged on the outer wallof the suspension pup joint; and the wall thickness of the transition section is gradually reduced from the middle section to the two ends of the suspension short section. According to the utility model, the thickened suspended marine riser and the variable cross-section design are adopted; the adaptive capacity of the suspended marine riser to environmental conditions is improved; a ball joint is arranged between the suspension short section and the conventional riser; local stress concentration possibly caused by structural rigidity difference between the suspension pup joint and the marineriser is avoided, when the suspension marine riser inclines under the action of ocean current, bending moment is released at the position of the ball joint, the suspension pup joint can still be keptin a vertical state basically, and safety of the system is guaranteed.