In response to industry challenges such as the excessive length-to-width ratio of air conditioner indoor unit packaging boxes leading to a decline in compressive strength and the possibility of bulging or concave deformation during storage and transportation, the research focuses on exploring high-compressive-strength corrugated cardboard boxes through structural innovation. Starting from the mechanism of structural failure, the 04 type box was selected as the key research object. Then, typical 0201 type, 0203 type, and 0440 type modified boxes were selected, and samples were made using ordinary and reinforced five-layer BC corrugated board. Systematic tests were conducted on edge compressive strength, empty box compressive strength and simulated real storage stacking experiments. Combined with mechanical properties, cost, and production processes, a multi-dimensional comprehensive evaluation was carried out. The experiments show that the 0440 type modified box, with the integral bottom plate and multiple force-bearing plates structure, exhibited the best compressive strength and can fundamentally solve the problem of weak long sides of the box, making it suitable for high-end applications with high packaging strength requirements. After the 0201 type box being equipped with U-shaped support plates, its compressive strength also significantly improved, and its compressive efficiency was significantly better than that of the ordinary 0201 type box and 0203 type box. In conventional application scenarios, it has a higher cost-performance ratio. The above conclusion provides data support and decision-making basis for the structural selection of air conditioner wall-mounted unit packaging.