The invention discloses a plastic foaming honeycomb composite board, which at least comprises a supporting main body and a plastic panel. The supporting main body at least comprises a supporting core, and the supporting core has a honeycomb structure and is formed by processing a plastic foaming material. The plastic panel is fixedly connected and supported on the supporting main body, and the supporting core is fixedly connected with the plastic panel. Compared with the prior art, because the supporting core has the honeycomb structure and is formed by processing the plastic foaming material, the composite board has the following advantages: the honeycomb structure made by the plastic foaming material has high supporting strength and lower manufacture cost; the materials of the supporting core, the plastic panel and a plastic bottom board belongs to the same class, so as to be welded or struck firmly without separation; the materials have the same heat expansion coefficient, so as to prevent separation caused by the expansion on heating and contraction on cooling; the honeycomb structure made by the plastic foaming material can be formed one time; and the supporting cores with regular or irregular shapes can be directly formed..