In this paper, the effects of in-line coagulation on permeation flux (PF), fouling resistance (FR), and total organic compound (TOC) rejection (R) of synthesized mullite ceramic membranes during treatment of oily wastewater in coagulation - MF hybrid process were investigated. Four coagulant ((ferrous chloride (FeCl2 center dot 4H(2)O), ferrous sulphate (FeSO4 center dot 7H(2)O), aluminum chloride (AlCl3 center dot 6H(2)O) and aluminum sulphate (Al-2(SO4)(3)center dot 18H(2)O)) plus equal concentration of lime in the form of calcium hydroxide (Ca(OH)(2)) were evaluated in the coagulation - MF hybrid process at different concentrations (0 ppm, 25 ppm, 50 ppm, and 100 ppm). The results showed that coagulation can affect the membrane filtration by changing characteristics of the oil droplets. Coagulant agents improve the membrane performance at low dosage (25 ppm) for aluminum chloride and mean dosage (50 ppm) for ferrous chloride, ferrous sulphate, and aluminum sulphate. At the best conditions (50 ppm ferrous sulphate), PF increased from 2.22 x 10(-5) to 2.76 x 10(-5) (m(3)/m(2) s), FR decreased from 4.2 x 10(12) to 5.55 x 10(11) (m(-1)), and R increased from 93.8% to 97.1%.