Industrijalizacija, porast populacije i urbanizacija glavni su uzroci stvaranja sve većih količina komunalnih otpadnih voda (KOV) koje, neobrađene, predstavljaju ozbiljnu prijetnju prirodnim vodonosnicima. Radi zaštite okoliša i prirodnih resursa potrebno je primjenjivati visokoučinkovite i okolišu naklonjene tehnologije obrade KOV-a. Cilj ovog rada bio je obrada KOV-a naprednim membranskim postupcima; membranskim bioreaktorom (MBR) te dodatnom obradom MBR efluenta s nanofiltracijom (NF) i reverznom osmozom (RO). Laboratorijska i pilot-obrada KOV-a MBR-om rezultirala je smanjenjem kemijske potrošnje kisika (KPK), biokemijske potrošnje kisika (BPK5), mutnoće i suspendiranih tvari za više od 92 %. Mikrobiološki parametri smanjeni su za 4,12 log10 do 4,88 log10. Naknadna obrada MBR efluenta s RO/NF membranama (XLE i NF270) pokazala je dodatno smanjenje svih mjerenih parametara.; Industrialization, population growth, and urbanization are the main causes for the generation of increasing quantities of municipal wastewater (MWW) which, untreated, pose a serious threat to natural aquifers. In order to protect the environment and natural resources, it is necessary to use high-efficiency and environmentally friendly technologies for the treatment of MWW. The goal of this work was treatment of MWW with advanced membrane processes; membrane bioreactor (MBR) and nanofiltration (NF) and reverse osmosis (RO). Laboratory and pilot treatment of MWW with MBR resulted in a reduction of more than 92 % in chemical oxygen demand (COD), biochemical oxygen demand (BOD5), turbidity and suspended matter. The number of microbiological parameters decreased by 4.12 log10 to 4.88 log10. Subsequent treatment of MBR effluent with RO/NF membranes (XLE and NF270) further reduced all measured parameters.