In this work, one-factor-at-a-time experiments and factorial design were carried out in order to study the effect of operating conditions on the monoglycerides (MG) concentration using molecular distillation (MD) process in laboratory scale. Therefore, producers of distilled MG can use the results obtained here to optimize industrial plants. Firstly, a 2(4-1) factorial design was employed to select the most important operating variables of the process. Among the four variables studied, evaporator temperature (ET), feed flow rate (Q), feed temperature (FT) and condenser temperature (CT), just ET and Q are important at the experimental conditions studied. Furthermore, using empirical models and experimental data, it is shown the dependence of the outlet stream compositions to ET and Q, which were selected from the fractional factorial design.85A1115241528