Those peritectic alloys with large positive mixing enthalpy usually display metastable liquid phase separation. Here, the solidification kinetics for a model Fe50Cu50 alloy in broad cooling rate Rc range was predicted by phase-field simulations and confirmed by drop tube experiments. Near-equilibrium peritectic solidification occurs in small Rc regime below 5.62×102Ks−1. As Rc rises beyond 7.76×102Ks−1, metastable phase separation takes place and results in the formation of a dispersed structure. Afterwards, multilayer core-shell structures appear, and the layer-number varies from two-layer to six-layer with further increasing Rc. Once Rc exceeds 3.64×105Ks−1, a dispersed structure once again forms because the core-shell dynamic condition is not satisfied. Non-equilibrium peritectic solidification is induced if Rc is greater than 5.85×105Ks−1.