Abstract: A lab scale Sequencing Batch Reactor (SBR) was set up and operated to establish an Enhanced Biological Phosphorus Removal (EBPR) process. The reactor was fed with synthetic wastewater and activated sludge was recycled through alternating anaerobic and aerobic conditions. Seed sludge was collected from a conventional activated sludge wastewater treatment process. During the sludge acclimatization period, the performance of SBR was monitored periodically for the development of EBPR characteristic. Start-up period of about one month was required to acclimatize the seed sludge to establish EBPR. On day 8 of sludge acclimatization period, the system still showing characteristic of conventional activated sludge process where major part of carbon source were consumed during aerobic phase but not rapid carbon assimilation during anaerobic phase. The removal efficiency of organic matter and orthophosphate on day 8 were 80.4 and 14.9%, respectively. The trend of rapid carbon source assimilation and release of orthophosphate during anaerobic phase was getting significant started from day 19 to 28 of sludge acclimatization period. Efficiency of organic matter removal at the end of monitored cycles on day 19, day 24 and 28 were in the range of 70-80%. The efficiency of phosphorus (PO4-P) removal was improving from day 8 to 28, 14.9% of removal on day 8, 20.9% on day 19, 21.6% on day 24 and 51.7% on day 28. Under microscopic analyses, the presences of gram-negative coccibacilli resemble Polyphosphate Accumulating Organismss (PAOs) detected when EBPR established. Both chemical and microscopic analyses supported the enrichment of PAOs in the SBR within a relatively short sludge acclimatization period. Thus, it is feasible to establish EBPR process by using seed sludge from conventional activated sludge process.