Photoemission and x-ray absorption measurements have been performed on Er5Ir4Si10, a compound that exhibits an incommensurate charge-density-wave formation below 155 K. The resonant photoemission and x-ray absorption measurements performed across the Er N-54 and Er M-5 edge identify the Er 4f multiplet lines, the 4f occupancy and the character of the states close to the Fermi edge.