The invention discloses a preparation method of degradable metal molybdenum and alloy for ureteral and urethral stents. The alloy comprises the following components in percentage by mass: 0.2-17 wt% of Zn, 0-6 wt% of Fe, 0.2-17 wt% of Mg and 0-15 wt% of Cu, and the rest metal is Mo. The elements such as Mo, Zn, Fe, Mg, Cu and the like are uniformly mixed, and vacuum arc melting is performed to obtain the alloy. The molybdenum-based alloy has good mechanical properties and is easy to process, and the properties such as strength, toughness and plasticity meet the requirements of human body implant materials for biliary tracts and the like. The surface of the stent is coated with anti-stenosis, anti-urethral infection, antibacterial and other polymer drugs. The five elements of Mo, Zn, Fe, Mg and Cu are the elements necessary for a human body, magnesium is an activating agent and an auxiliary factor of various enzymes, zinc ions participate in in-vivo balance and immune reaction, iron is a main substance for maintaining life and is an important component of hemoglobin of the human body, a degradation product of copper has a certain antibacterial effect, and molybdenum can prevent anemia and promote development. The molybdenum-based alloy ureteral and urethral stent has good biological performance, and the degradation process and the product are safe and effective to a matrix.