The reference interaction site model (RISM) theory combined with the generalized Langevin/mode-coupling theory (MCT) is applied to the investigation of solvation dynamics in water. The dynamic response function S S (t) which measures the energy relaxation of the system is calculated with different model solutes. The RISM–MCT framework recently presented by Yamaguchi and coworkers [J. Chem. Phys., 117 (2002) 2216; Mol. Phys., 101 (2003) 1211] is shown to be applicable well to the realistic description of solvation dynamics. S S (t) initially relaxes with a Gaussian decay followed by an overdamping oscillation with the time period of 30 fs. As the multiplicity of the solute pole is increased, the magnitude of the S S (t) damping becomes smaller and relaxation gets slower.