The invention discloses a split support structure for a turboshaft engine dual-rotor experimental bench comprising a squirrel-cage elastic support, a squeeze film damper, a side-by-side antifriction bearing, a bearing support and tenoned end face oil baffle rings. The squirrel-cage elastic support, the squeeze film damper and the bearing support are all split structures, and the split surfaces arevertical planes passing through the centerline of a shaft. The squeeze film damper and the squirrel-cage elastic support are installed on the bearing support. The side-by-side antifriction bearing isinstalled in the squeeze film damper and a shaft is supported on the side-by-side antifriction bearing. Two parallel oil baffle ring grooves are arranged on the outer ring of the side-by-side antifriction bearing. The tenoned end face oil baffle rings are arranged in the two oil baffle ring grooves. The split support structure is simple, the squirrel-cage elastic support, the squeeze film damper,the bearing and the bearing support can be split, and the bearing support can be replaced easily without disassembling the rotors of the turboshaft engine dual-rotor experimental bench.