Anaerobic membrane bioreactors (AnMBR) have been established as an efficient method of wastewater treatment to obtain high-quality effluent with low energy consumption. However, membrane fouling leading to flux reduction and an increase in operational costs can negate potential benefits associated with AnMBR. Today’s conventional membrane cleaning process includes physical and chemical approaches, both of which have their own drawback. For this reason, the biological approach was proposed as an alternative to dangerous, energy-consuming, and environmentally unsafe treatment techniques. The combination of UV-C and bacteriophage offers an alternative chemical-free approach for biofouling control. This dissertation aims to test the different order of using UV-C and bacteriophage to clean anaerobic membrane. This dissertation also demonstrates a proof-of-concept to achieve semi-online cleaning using UV-C and bacteriophage, thus increasing the feasibility of described technology. As a result of this work, it was shown that preliminary UV exposure enhances bacteriophage propagation into thick biofilms, and that the bacteriophages are able to affect total cell number and extracellular polymeric substances (EPS) compared to the control. Compared to the control, the semi-online cleaning strategy also resulted in a membrane that took a longer time for the transmembrane pressure to increase in the next operation cycle after cleaning.