The separation of reactive Red 3BS ions across supported liquid membrane (SLM) process using tridodecylamine as a carrier and sodium hydroxide as a stripping agent was studied. A microporous polypropylene membrane fabricated using thermally induced phase separation technique was used as a membrane support for the SLM process. Three polymer concentrations (10, 15, and 20 wt%) and two quenching temperatures (7 and 29°C) were applied for the polymer-diluent solution. The results demonstrated that all membranes appeared with similar morphologies but different in pore size and porosity. The membrane with 15 wt% polymer concentration quenched at 29°C produced a microporous membrane with a symmetric structure, defined pore size, and performed high stability toward reactive dye extraction, thus feasible to be used as the support material. This membrane had successfully removed and recovered almost 100 and 58% of Red 3BS from an aqueous solution, respectively. Besides, it also exhibited high stability up to 25.5 h of extraction, hence demonstrating an improved performance for the separation of reactive dyes using SLM process.