The ultrafast electronic relaxation and the hydrogen-bond-formation/dissociation dynamics of photoexcited all-trans retinal in 1-butanol/cyclohexane mixed solvents have been studied by femtosecond time-resolved visible absorption spectroscopy. Four transient absorption bands, which can be assigned to the S-3, S-2, S-1, and T-1 states, were observed in neat cyclohexane. The shapes and the dynamics of these absorption bands agree very well with those reported previously for all-trans retinal in hexane. In contrast, only three transient absorption bands, which can be assigned to the S-3, S-2, and T-1 states, were identified in the mixed solvents. The band assigned to the S-2 State showed a time-dependent peak shift, which is attributed to solvent reorganization on a picosecond time scale. A kinetic analysis of the three transient absorption bands has led to the conclusion that no state-ordering change of the (n, pi*) and (pi, pi*) states takes place in the excited singlet manifold upon hydrogen-bond formation. The l-butanol concentration dependence of the absorption spectra shows that the free and hydrogen-bonded species coexist in the S-3 and T-1 states, but that all of the retinal molecules are hydrogen-bonded in the S-2 state. These observations indicate that an ultrafast hydrogen bond-formation reaction takes place during or just after the S-3 --> S-2 internal conversion and is complete within a time scale much shorter than the S-2 lifetime. Dissociation of the hydrogen bonding is most likely to take place during or after the S-1 --> T-1 intersystem crossing and is complete within a time scale much shorter than the T-1 lifetime. The observed longer lifetime of the hydrogen-bonded S-2 State is consistent with the higher isomerization quantum yield in protic solvents than in aprotic nonpolar solvents.