The dynamic solvent effect on the intramolecular conformational change accompanying charge-transfer in the excited state has been investigated in alcohol solvents by using the steady-state as well as picosecond time-resolved fluorescence spectroscopy as a function of pressure. The result of the experimental research aimed at understanding the coupling between the dynamics of the intramolecular twisting motion of solute and the solvent relaxation is described. The magnitude of viscosity dependence varies with increasing solvent viscosity by applying high pressures. The behavior referred to as the “pressure tuning effect” of solvent viscosity on intramolecular charge-transfer (ICT) reaction in the excited  state is comparatively discussed for three ICT  forming molecules. It has been confirmed that  the longitudinal relaxation time of solvent  obtained from low temperature source well reflects the solvent relaxation time at high  pressures.