The phase diagram of the Al–Ce–Cu system in the aluminum-rich corner (concentrations up to 35wt.% Cu and up to 16wt.% Ce) was studied. Phases and invariant reactions were identified. Liquidus and solidus surfaces, three isothermal cross-sections (540, 590 and 200°C) and five vertical cross-sections were constructed. It was shown that Al₄Ce (Al₁₁Ce₃), Al₈CeCu₄ and Al₂Cu were in equilibrium with the aluminum solid solution (Al). It was determined that about 17wt.% Cu dissolves in Al₄Ce; the existence of the Al₄CeCu phase was not confirmed. Experimentally determined parameters of the invariant quasi-binary eutectic reaction L→(Al)+Al₈CeCu₄ (610°C, 14wt.% Cu and 7wt.% Ce) were essentially different from those published earlier. This eutectic had a fine microstructure and was stable to coarsening (after fragmentation and spheroidizing) during the heating process even though the average particle size did not grow larger than 2μm after annealing at 590°C.