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Experiments for acetic acid hydrogenation and catalyst characterizations were conducted to study the kinetics of hydrogenation and esterification over PtSn impregnated on Al 2 O 3 catalyst (PtSn/Al 2 O 3 ), K doped on PtSn/Al 2 O 3 catalyst (K/PtSn/ Al 2 O 3 ), and PtSn impregnated on K/Al 2 O 3 catalyst (PtSn/K/ Al 2 O 3 ). Kinetic parameters such as activation energy, dissociation enthalpy, and adsorption heat of elementary reaction for hydrogenation and esterification were determined on the basis of Langmuir−Hinshelwood model. After the addition of 0.5 wt % K to PtSn/Al 2 O 3 , activation energy of hydrogenation decreased from 20.8 to 11.5 kJ/mol and activation energy of esterification increased from 22.3 to 31.7 kJ/mol. The results of dissociation energy and adsorption heat reflect that K/PtSn/Al 2 O 3 can improve spillover of hydrogen and desorption of ethanol. PtSn/K/Al 2 O 3 had the opposite effect. Potassium also enhanced dissociation of C−OH bond to form more acetyl species. Good agreement was obtained upon comparison of the experimental and calculated data.