This study was conducted to determine optimum design parameters in nitrification and denitrfication of chemical fertilizer wastewater using pilot plant, Jet Loop Reactor. The chemical fertilizer wastewater which contains low amounts of organic carbon and has a high nitrogen concentration requires a post-denitrfication system. Organic nitrogen is hydrolyzed above $86\%$, and the concentration of organic nitrogen was influent wastewater 126mg/L and of effluent wastewater 16.4mg/L, respectively. The nitrification above $90\%$ was acquired to TKN volumetric loading below $0.5;kgTKN/m^3{cdot}d$, TKN sludge loading below $0.1;kgTKN/kgVSS{cdot}d$ and SRT over 8days. The nitrification efficiency was $90\%$ or more and the maximum specific nitrification rate was $184.8;mgTKN/L{cdot}hr$. The denitrification rate was above $95\%$ and the concentration of $NO_3-N$ was below 20mg/L. This case was required to $3;kgCH_3OH/kgNO_3-N$, and the effluent concentration of $NO_3^--N$ was below 20mg/L at $NO_3^--N$ volumetric loading below $0.7;kgNO_3^--N/m^3{cdot}d$ and v sludge loading below $0.12;kgNO_3^-N/kgVSS{cdot}d$. At this case, the maximum sludge production was $0.83;kgTS/kgT-N_{re}$ and the specific denitrfication rate was $5.5;mgNO_3-N/gVSS{cdot}h$.