Currently, utilization of waste by-products or waste materials have received attention globally as it brings significant economic and environmental impacts. In this study, palm oil clinker (POC) which is one of the waste by-products generated in the processing of palm oil was utilized as submerged fixed media in Sequence Batch Reactor (SBR). By using POC as filter media for wastewater treatment, it is able to extend the useful life of POC and reduce the demand manufacturing new media. SBR is a fill-and-draw type reactor system which allow all activated sludge process to occur over a series of time in a single complete-mix reactor. During the operational steps of SBR, the combined attached growth/activated sludge system will promote the growth microorganism that attached on the media in the activated sludge process to remove pollutants such as organic matters and nutrients passes through the media. Laboratory-scale of two Sequence Batch Reactors (SBR) was fabricated with one of the reactors filled up with POC submerged fixed media. Influent of domestic wastewater from Universiti Teknologi Petronas (UTP) 's Sewage Treatment Plant (STP) was adopted for wastewater treatment. Based on the result obtained, SBR reactor with POC submerged fixed media has higher ammonia removal efficiency, which approximately 90 than the SBR reactor without POC submerged fixed media, which approximately 85. © Published under licence by IOP Publishing Ltd.