A model for the disordering of GaAs/AlAs-superlattices during zinc diffusion, which is consistent with recently established models for gallium self-diffusion and zinc diffusion in GaAs, is presented. Four coupled partial differential equations resulting from the model are solved numerically. In accordance with measured data in the literature, no disordering without zinc can result for temperatures around 600°C. Zinc diffusion, however, produces a large amount of gallium self-interstitials, which leads to a complete disordering of superlattices with a period thickness of 32 nm to a depth of about 0.8 μm within one hour. The used values for the diffusion coefficient and the equilibrium concentration of gallium self-interstitials are a consistent splitting of the gallium interstitial dominated self-diffusion coefficient.