In this paper, dividing wall column (DWC) has been chosen for a BTX (Benzene-Toluene-o-Xylene) system. A MATLAB ® program has been written for nonlinear unsteady-state DWC, which is used in Simulink environment for control of the system by Model Predictive Control (MPC). Compositions of the three products (benzene, toluene, and o-xylene) are indirectly controlled by controlling the corresponding temperatures of the respective tray due to requirement of online analyzer. The temperature of uppermost tray in the rectifying section, stage temperature in the main column corresponding to the side stream withdrawn, and the bottom stage temperature in the stripping section have been chosen in order to maintain the compositions of the three products. The manipulated variables are reflux rate (L 0 ), side-stream flow rate (SSRF), and reboiler heat duty (Q B ). It has been observed that MPC shows good performance even in the presence of ± 10% change in the feed flow rate, feed composition, and liquid split factor in comparison with conventional controllers. The MPC has less settling time (almost 1.5 h) compared with the PI controller (approximately 3-4 h).