Underwater structure of ultra-wide floating platform

The utility model belongs to the technical field of ocean engineering, and particularly relates to an ultra-wide floating platform launching structure which is used for launching of a floating platform and comprises a wharf, a launching barge parked on the side of the wharf and building slipways including a first building slipway and a second building slipway. A first building slipway launching slideway is arranged on the first building slipway, and a second building slipway launching slideway is arranged on the second building slipway; the ultra-wide floating platform is borne on the building ship platform; the launching trolley system is arranged between the building slipway and the ultra-wide floating platform, and the launching trolley system slides in the first building slipway and the second building slipway to pull and move the ultra-wide floating platform from the building slipway to the wharf; and the ultra-wide floating platform is transferred to the launching barge through the wharf, and the launch