Most models developed in the past for gas-liquid absorption accompanied by chemical reactions assumed isothermal conditions for an easy treatment of the experimental data. The reactions are often highly exothermic accompanied by a substantial temperature increase at the interface which affects not only the rate constants, but also the solubilities as well as the diffusivities. Analytical expressions are derived in this work to describe the diffusion-convection-reaction of a reacting solute component in a reactant solution in a hollow fiber membrane contactor in which the shell hydrodynamics is assumed as a plug flow. Results are presented for a classical bimolecular nonisothermal reaction to illustrate the effects of various parameters on the enhancement factor, efficiency, and temperature rise. The volatility effect of the liquid phase reactant on the absorption efficiency is also illustrated.