This study was conducted to develop a new RBC process available for the effective removal of organic matters and nitrogen in sewage. The RBC process for the oxidation organic compounds and nitrification was designed to occur at the 1st-stage and next-stage RBC respectively. Then nitrified water was recycled to the denitrifying RBC located at the lower part of the 1st-stage RBC. Some results were summarized as follows. 1. The loading limitation was represented as $60g{\cdot}COD/gm^2/day$ in experiment of simultaneous removal of organic matter and nitrogen. The maxmum COD % removal was 85% at the load $35g{\cdot}COD/m^2/day$. 2. The $NO_3-N$ % removal was approximately 80% at the load $60g{\cdot}COD/m^2/day$ and the maximum $NO_3-N$ remaval rate was $3.9g{\cdot}COD/m^2/day$ and the overall C/N ratio of 11.0 as required to achive 80% of $NO_3-N$% removal. 3.$NO_3-N$ removal rate was rapidly decreased above the load $7g{\cdot}NH_4{^+}-N/m^2/day$ and the maximum $NO_3-N$ removal rate was $3.7g{\cdot}NO_3-N/m^2/day$. 4. Irrespective of the recycle ratio, the COD % removal at the system of 2-stage RBC unit was nearly constant as 89% while the maximum one in the 1st-stage unit was 77% in the case of 50% recycle. 5. The maximum COD % removal in the 3-stage RBC system was 93% while 1st-stage one being 80%, under the $NH_4{^+}-N$ load of $7.4g/m^2{\cdot}d$. Also maximum percentage of nitrification and denitrification was 69% and 41% respectively, under the same $NH_4{^+}-N$ load.