The substitution effect on the dynamics of the proton transfer in thermochromic salicylideneanilines in the crystalline phase was investigated using femtosecond time-resolved fluorescence spectroscopy. From the deuteration effect and low-temperature measurement, it is concluded that the proton tunnels the potential barrier quantum-mechanically in the excited state. The rate of proton transfer was found to decrease with the energy separation between the excited enol and keto forms due to the different potential-barrier heights. The change in the potential-barrier height is qualitatively explained by the electron-donating or -accepting property of the substituent around the hydrogen bond. The thermalization of the vibrational states of the excited enol form was also observed.