The Al-Cu-Fe-Mg-Si phase diagram was assessed in the Al-Cu-rich region, including the solidification reactions and the phase distribution in the solid state. With taking into account that all alloys in the examined region contain (Al) and Al2Cu phases, the phase diagram is plotted on the plane of concentration triangle, similar to the visualization of quaternary systems. The invariant eutectic reaction L => (Al) + Al2Cu + Mg2Si + Al7Cu2Fe + Al2CuMg was experimentally confirmed in the five-component system. The temperature and composition of the invariant eutectic point are close to those of the invariant reaction L => (Al) + Al2Cu + Mg2Si + Al2CuMg observed in the quaternary system.