The aim of this study was to investigate the performance of a Moving Bed Sequencing Batch Biofilm Reactor (MBSBBR) with regard to organic matter removal and nitrification. Within the scope of this study, the kinetic constants for organic matter removal and nitrification in a lab-scale MBSBBR fed with a synthetic influent of domestic wastewater characteristics were determined. The evaluation of the results revealed that removal of organic matter at high rates and with efficiencies over 90% was secured at all operational conditions applied. Full nitrification was obtained with a rate of 0.241 g NOX-N/m(2).d(-1) at 20 degreesC. The autotrophic growth rate was determined to be 0.50 d(-1).