A comparison of computer simulation results of reactive distillation obtained by ASPEN PLUS and HYSYS software was done. Esterification of acetic acid and 1-butanol was chosen as the model reaction proceeding in a reactor and reactive distillation column (RD) system. A nearly equimolar reaction mixture was fed into the equilibrium fixed bed reactor and the liquid product was continuously fed into reaction zone of the reactive distillation column. The same mass balance in the reactor and reactive distillation column was used to compare the adequacy of chosen simulation systems. The results of computer simulation have been consequently compared with pilot plant experimental data. A good agreement was reached.