An optimum set of operating conditions which implies the regeneration energy of spent absorbent is minimum, is searched for in a CO2 recovery process employing chemical absorption. The relationship between the regeneration energy and such operating parameters as degree of CO2 removal and CO2 loading of absorbent, and steam quantity required for the regeneration of absorbent is examined. Optimum values of the parameters are calculated. The calculated results on the optimum set of operating condition for absorbents comprising novel hindered amine, agreed well with the experimental ones. The operation at the degree of CO2 removal below 90% was proved to be more energy-efficient.