© 2015 Balaban Desalination Publications. All rights reserved.Abstract: The objective of this study was to investigate the treatment of highly polluted tannery wastewater using ceramic microfiltration (MF) and ultrafiltration (UF) membranes. The impact of membrane pore size and pressure on permeate flux, chemical oxygen demand (COD), and color reduction was examined. All experiments were performed at a lab-scale, using cross-flow ceramic membrane test unit. Three different single-channel tubular ceramic membrane modules (γ-Al2O3, Media, and Process Technology, Inc., USA) with average pore sizes of 10, 50, and 200 nm were used. Wastewater sample was obtained from the effluent of tannery at organized industrial district of the city of Isparta, Turkey. Clean water flux tests were conducted before and after wastewater treatment. Permeate flux was reduced due to membrane fouling after all operation and fouling was removed effectively using chemical cleaning procedures. More than 95% color removal was consistently achieved with both UF membranes (10 and 50 nm). COD reductions ranged between 58 and 90% at all pressures for UF membranes tested in the wastewater. As the test pressure of the UF ceramic membranes increased, COD and color reduction also increased. It was concluded that ceramic UF membranes with 10 nm average pore size can be used in removing COD and color from highly polluted tannery wastewater.