The present study evaluated the efficiency of starch wastewater treatment through coagulation/flocculation using extracts of Moringa oleifera (M.O.) seeds as a natural coagulant. The experiments were performed following a Rotatable Central Composite Design (RCCD). The studied variables were: M.O. concentration and sodium chloride (NaCl) solution concentration. The response variables analysed were: Turbidity, Apparent Colour, COD and Cyanide Ion. The operational conditions optimized by the statistical program were: M.O. concentration of 2,484 mg L-1 and saline concentration of 0.9 mol L-1. Under these conditions the removal estimates are 89.16 % (turbidity), 54.43 % (apparent colour), 66.39 % (COD) and 9.9 % (cyanide ion).