The present invention provides a multi-layer composite seamless overall plastic tube, the tube wall comprises a first end surface and a second surface, both are slant end surface, and the slant angles are complementary angle relatively, the first and the second end surface are completely matched and opposite joint fixed, the hierarchical structure of the tube wall comprises a plastic printing layer, a first binding layer, a water-oxygen isolation layer, a second binding layer and a plastic heat sealing layer, the first binding layer bonds the plastic printing layer and the water-oxygen isolation layer, the second binding layer bonds the water-oxygen isolation layer and the plastic heat sealing layer, the invention also provides a preparation technique for the multi-layer composite seamless overall plastic tube, the inventive multi-layer composite seamless overall plastic tube external appearance has no appreciable soldering joint, high overlap joint intensity, durable ability, beautiful appearance, good handfeel, easy print, thus overcoming defects of having soldering joint of the multi-layer composite overall plastic tube, and defect of simplex function of single layer extrusion tube is overcome by the multi-layer compound structures.