A mathematical model of wastewater treatment in a sequencing fed-batch reactor based on Activated Sludge Model No. 1 has been developed. Experiments were performed in a laboratory bioreactor of 2 dm(3) volume. The fed-batch process lasting 9 hours has been investigated. The model parameters were estimated to best fit the experimental results, and the sensitivity analysis of the model parameters has been performed. The ability of SFBR for wastewater treatment is discussed.