Korea is currently classified as a water shortages countries, one of the most serious nations among the OECD countries experiencing water shortages, In the case of natural water resources, the temporal or spatial change of the quantity is very large, however reused treated wastewater is suitable for reuse due to its constant quantity throughout the year, Thus treatment characteristics study was performed treatment characteristics in IJBBP(Up-flow Biostyr Biofilter Process) in this study for reusing treated wastewater. The following conclusions can be drawn from the study: In the UBBP treatment characteristics, the results from operating UBBP indicated that the removal efficiency of CODcr was 40.8. 36.0. and 4.8 percent according to biofilter BFI. BF2 and SF3, respectively, therefore, the average removal efficiency of CODcr in whole system was XI .9 percent. Also, SS concentration of Influent was average 1 19.5mgIL and the effluent concentration was average I .4mglL, Therefore, the average removal efficiency was 98.7 percent during the study periods, SS removal efficiency was revealed 10 linear function in the IJBBP, DO concentration was increased to 6.6mglL in the SF1, and it was decreased to 5.Smg/L and 4.8mgfL in the SF2 and SF3, respectively. This phenomenon was caused by oxidation of organic matter and nitrification.