Multiphase droplet-based and continuous liquid-liquid extraction (LLE) of phenol from oil is studied in a low width-to-height aspect ratio polymethylmethacrylate (PMMA)-based microchannel reactor. The extraction efficiency of phenol from the dispersed phase consisting of silicone oil to the external continuous water phase is studied as a function of the flow rate ratio of the two immiscible phases. This paper demonstrates that for enhancing the extraction efficiency of phenol from silicone oil to water in droplet-based microfluidic reactors, a low flow rate ratio of the external continuous phase, Q(c), to dispersed oil phase, Q(d), is preferable.