Abstract: Objective The finite element method was used to study the self-expansion performance of composite braided stents in vessels with different degrees of stenosis, evaluating their behavior in complex physiological environments, and providing theoretical support for stent optimization and clinical application. Methods Nickel-titanium alloy (NiTi) and biodegradable magnesium alloy (JDBM) wires were braided into composite stents in three different ratios (24:0, 12:12, 8:16). The expansion process of the stents in arteries with 30%, 40%, and 50% stenosis was simulated to evaluate their expansion performance and the stress distribution on the plaque surface. Results After expansion, the maximum stress of the plaque was concentrated at the site of the most significant stenosis. Under full nickel-titanium alloy, the average maximum stress values for the plaque and stent were 0.24 MPa and 140 MPa, respectively. For the composite braided stents, these values were 0.41 MPa and 515.9 MPa, with the maximum stress appearing on the JDBM wire. JDBM wires enhanced the radial support performance of the stent, and at a 50% stenosis rate, the expansion ability of the stent containing 16 JDBM wires was 5% higher than that of the bare NiTi stent. Conclusion JDBM magnesium alloy wires enhanced the stent""s strength, support, expansion. The research results provide new ideas for the design of composite braided stents.