Reaction dynamics on excited states of two kinds of enols (Z and E) for 2-methylbenzophenone (MBP), which are produced through an intramolecular hydrogen abstracting reaction with the 308-nm laser irradiation, has been studied in ethanol solution with stepwise two-color excitation time-resolved thermal lensing (TC-TRTL) and stepwise two-color excitation transient absorption techniques. When the E-enol was solely excited with the 532-nm laser, the increase of the transient absorption was observed at less than 420 nm, while no spectral change appeared for excitation of the Z-enol. It reveals that only the E-enol does react after the excitation to presumably produce dihydroanthrone (DHA). The heat of reaction was successfully determined by the TC-TRTL method, and the reaction was found to occur endothermically. The candidates for the photoproduct were also discussed.