Partial　denitrification　(PD,　NO3--N　-＞　NO2--N)　provides　a　promising　opportunity　for　anammox　application　in　wastewater　nitrogen　removal.　In　this　study,　a　continuous-flow　PD/Anammox　(PD/A)　process　operated　with　a　novel　gas　mixing　was　reported　in　an　up-flow　anaerobic　bed　reactor.　A　high　nitrogen　removal　rate　of　2.42　kgN/(m(3).d)　was　achieved　at　a　relatively　short　hydraulic　retention　time　(HRT)　of　0.5　h　with　both　influent　NH4+-N　and　NO3--N　of　30　mg/L.　Sludge　floatation　was　eliminated　by　mixing　with　gas　of　the　reactor　due　to　an　efficiently　improved　mass　transfer.　Further　optimization　of　gas　flowrates　at　high　NLR　could　avoid　the　overproduction　of　fight-bound　extracellular　polymeric　substances　(TB-EPS)　and　benefit　sludge　stability.　Functional　microorganisms　of　PD　and　anammox　were　effectively　retained,　and　Zoogloea　affecting　sludge　settleability　kept　increasing　throughout　the　operation.　This　study　clearly　demonstrated　the　effectiveness　of　gas　mixing　strategy　for　a　high-rate　continuous-flow　PD/A　process　with　stable　nitrogen　removal　performance.