The invention discloses an Mg-Y-Nd-(La+Ce)-Zr biodegradable magnesium alloy and a manufacturing method thereof. The Mg-Y-Nd-(La+Ce)-Zr biodegradable magnesium alloy is characterized in that the magnesium alloy is manufactured from the following components in percentage by mass: 3.0-4.5% of Y, 2.0-3.5% of Nd, 0.3-1.0% of Zr, 0.05-0.5% of lanthanum cerium composite rare earth, and the balance beingmagnesium and inevitable impurities, wherein the impurity content is less than or equal to 0.1%, and lanthanum content and cerium content in the lanthanum cerium composite rare earth each account for50%; and the manufacturing method comprises the steps: batching, casting, annealing, extruding, and obtaining finished products. According to the magnesium alloy and the manufacturing method, a multi-element and small-amount design method is adopted, the proportion is scientific and reasonable, the manufacturing process is simple, the manufactured magnesium alloy is high in compactness, reliable in quality, excellent in mechanical property and corrosion resistance, controllable in degradation speed and excellent in biocompatibility, meanwhile, a cardiovascular stent made of the magnesium alloycannot be damaged for deformation and can be well matched with human tissues, and therefore the magnesium alloy has wide application prospects in the medical field.