Objective To explore the mechanical properties of the hybrid patch made of porcine acellular small intestinal submucosa (P-SIS) and polydioxanone (PDO) and its effect on repairing the abdominal wall defects of rats.Methods The PDOSIS patch and 8SIS patch were constructed by weaving and vacuum lamination and the mechanical properties were measured.In the both sides of abdomen of 36 healthy female SD rats,a partially defect (lcm × lcm) was created by surgery and repaired with a same area of PDO-SIS patch or 8SIS patch,each 12 rats were randomly sacrificed at 2,4 and 8 weeks after surgery,respectively,and tissue regeneration was evaluated.Results The bending length and tensile strength of the PDO-SIS patch were stronger than the 8SIS patch (P＜0.05) with the increase of diameter.No acute inflammation occurred at the repaired sites of the two groups,but a moderate chronic inflammation was observed 2 weeks after surgery,and the inflammatory response reduced gradually over time,no obvious chronic inflammation was found in the 8th week after surgery,with no statistical differences between the two groups (P＞0.05).Two patch materials were degraded gradually in the repaired area,and the regenerated collagen tissues were deposited continuously,but no significant differences existed between the two groups in the collagen content and collagen arrangement (P＞0.05).Conclusion The PDO-SIS patch has better mechanical properties than the 8SIS patch,and does not cause strong immune rejection when used to repair abdominal partially defect of SD rats.