The　innovative　DEnitrifying　AMmonium　OXidation　(DEAMOX)　process,　coupling　partial-denitrification　(PD)　with　anammox,　was　designed　for　treating　high-strength　nitrate　(NO3--N)　and　ammonia　(NH4+-N)　wastewater　for　the　first　time.　With　influent　total　nitrogen　(TN)　up　to　1600　mg　L-1　(NO3--N/NH4+-N　of　1.0),　DEAMOX　process　proved　to　be　relatively　stable　for　simultaneously　removing　NO3--N　and　NH4+-N.　The　step-feeding　organic　carbon　(OC)　demonstrated　as　an　efficient　strategy　for　avoiding　NO2--N　consumption　by　denitrification,　facilitating　the　increased　of　NO3--N　to　NO2--N　transformation　ratio　(NTR)　to　99%　at　COD/NO3--N　of　1.77.　The　TN　removal　was　significantly　enhanced　to　96.7%　with　the　considerably　high　anammox　contribution　of　88.9%.　Also,　the　inhibitory　effect　of　high　NO2--N　accumulation　on　denitrifying　bacteria　could　be　mitigated.　High-throughput　sequencing　revealed　a　relatively　stable　cooperation　of　functional　groups　in　DEAMOX　system.　Genus　Thauera　possibly　capable　of　NO2--N　accumulation　remained　dominant　(39.81%　to　44.09%),　while　Candidatus　Brocadia　responsible　for　anammox　was　detected　with　much　lower　percentage　(2.01%　to　1.81%).　Results　of　qPCR　confirmed　the　evident　growth　of　anammox　bacteria　under　increasing　nitrogen　and　organic　loading.　The　DEAMOX　process　offers　a　significantly　stable　and　efficient　method　in　treating　high-strength　NO3--N　and　NH4+-N　wastewater.