The invention discloses a light composite connecting skirt and a forming method thereof. The connecting skirt comprises a connecting area on the upper portion, a force bearing area in the middle and a bonding area on the lower portion, and connecting holes are formed in the connecting area in the circumferential direction at intervals. An outer
glass fiber layer is integrally laid on the outer surfaces of the connecting area, the force bearing area and the bonding area, and an outer
skin is integrally laid on the inner surface of the outer
glass fiber layer; ribs in grid arrangement are arranged on the inner surface of the outer
skin corresponding to the bearing area; reinforcing blocks are arranged on the inner surface, corresponding to the connecting area, of the outer
skin, the reinforcing blocks are embedded in gaps of the ribs arranged in a grid mode, and hollow cylindrical inserts are embedded in the positions, corresponding to the connecting holes, in the reinforcing blocks; filling blocks are arranged on the inner surface, corresponding to the bonding area, of the outer skin, and the filling blocks are embedded in gaps of the ribs arranged in a grid mode. On the basis of ensuring the overall structural strength and the load transmission coherence, not only is the mounting convenient, but also the maximum weight reduction is realized.