Valence electronic states of third‐period elements (Al, Si, P, and S) dissolved in Cu were pursued through the chemical effect of the LVV Auger transition from these elements using Auger electron spectroscopy (AES). Indeed, the LVV Auger signals of Al, Si, P, and S in Cu hosts differed completely from those in the pure (metal or semiconductor) states, indicating the presence of the definite chemical effect. The origin of the chemical effect was discussed in connection with similar studies by soft x‐ray spectroscopy (SXS).