The invention provides a marine ultra-large type floating body connecting mechanism. The mechanism comprises a plurality of telescopic devices connected between ultra-large type floating bodies; when two ultra-large type floating bodies relatively rotate within a horizontal plane, all distributed telescopic systems perform telescopic movement in the opposite directions on the basis of the rotating direction of the ultra-large type floating bodies with the middle line as a symmetric axis, that is, a telescopic system on one side is pressed, a telescopic system on the other side is pulled, and the same buffer function is realized. The acting force generated during movement of the ultra-large type floating bodies is dispersed by the arranged telescopic devices, and the strength requirements of the connecting mechanism are reduced.