The　landfill　leachate　was　treated　by　supercritical　water　oxidation　technology　with　a　batch　reactor.　Central　composite　design　(CCD)　experiment　was　used　to　evaluate　the　effects　of　temperature　(400~500°C),　pressure　(24~28　MPa),　oxidation　coefficient　(1.5~2.5),　residence　time　(5~10　min)　and　their　interactive　effects　on　COD　and　NH4　+-N　removal　efficiencies,　and　the　quadratic　regression　models　were　obtained　by　the　response　surface　analysis.　Results　indicated　that　the　effects　on　COD　removal　efficiency　were　in　the　order:　pressure＞　temperature＞　oxidation　coefficient＞　residence　time,　and　that　the　order　on　NH4　+-N　removal　efficiency　were　temperature＞　pressure＞　oxidation　coefficient＞　residence　time.　The　interactive　effects　on　both　COD　and　NH4　+-N　removal　efficiencies　were　not　significant.　The　forecast　error　of　the　quadratic　regression　models　on　COD　and　NH4　+-N　removal　efficiencies　were　less　than　±4%　and±9%,　respectively.　The　optimum　parameters　within　the　experimental　range　were:　496.05　°C,　27.69　MPa,　oxidation　coefficient　of　2.44　and　residence　time　of　5　minutes.　Under　the　optimized　conditions,　the　COD　and　NH4　+-N　removal　efficiency　can　reach　98.31%　and　95.69%,　respectively.