Abstract: Depleted zinc-64 can effectively reduce the radioactivity in the primary circuit of nuclear power plant. At present, centrifugal separation is an important method to prepare depleted zinc-64. In the process of separation of zinc, the centrifuge is easy to be blocked in cascade, which will affect the stable operation and product abundance of the cascade. Considering the situation that the scoops of some centrifuges in cascade are blocked, a cascade mathematical model with different flow and different overall separation factor is established, which is solved by the quasi-linearization method. Based on the derived calculation equation, the different numbers of blocked scoops of centrifuges in different stages is simulated. The calculation results of the simulation example show that the blocked scoops of centrifuges will reduce stability of cascade, resulting in 15% fluctuation of the flow, and the dilution abundance of the target component also fluctuates from 0.500 4% to 0.931 5%. The conclusion is helpful to guide the actual cascade design and operation.