OH stretching vibrations of phenol-(H₂O)_n (n=1, 3) in the S₁ state have been observed by UV-IR double resonance spectroscopy, where the fluorescence dip induced by the IR excitation was monitored. The spectra were analyzed by comparing with those of the S₀ state reported in a previous work. It was found that a frequency reduction of the phenolic OH stretching vibration and an enhancement of the interactions among the hydrogen bond network in the cluster were much larger in the S₁ state than in the S₀ state, representing the increase in acidity of phenol upon the electronic excitation. The nonradiative process of the vibrationally excited phenol is also discussed based on the fluorescence-dip spectrum of the deuterated phenol in S₁.