The　centrate　produced　from　a　thermal　hydrolysis　pretreatment　coupled　anaerobic　digestion　(THP-AD)　system　is　generally　characterized　by　high　concentrations　of　ammonium　and　recalcitrant　organics.　In　this　study,　a　costeffective　partial　nitritation-anammox　(PN/A)　process　was　developed　to　evaluate　the　potential　challenges　in　THP-AD　centrate　treatment.　The　results　show　ammonium　oxidizing　bacteria　(AOB)　and　anammox　bacteria　were　seriously　inhibited　by　THP-AD　centrate,　while　long-term　acclimation　together　with　aeration　optimization　can　mitigate　such　inhibition.　A　nitrogen　removal　rate　(NRR)　of　0.55　kg　N/m3/d　was　obtained　and　maintained　with　60%　THP-AD　centrate　as　feed.　However,　100%　THP-AD　centrate　caused　sludge　wash-out　from　PN　reactor　due　to　excessive　polymer　and　high　solids　in　influent.　The　alkalinity　deficit　also　reduced　the　AOB　activity.　Moreover,　anammox　activity　and　overall　NRR　also　declined　(to　0.37　kg　N/m3/d).　The　organics　transformation　mainly　occurred　in　PN　reactor　with　very　low　removal　efficiency　due　to　their　recalcitrant　characteristics.　The　humic　acidlike,　fulvic　acid-like　substances　and　building　blocks　were　revealed　as　the　major　organic　compounds　in　THP-AD　centrate　(51.5-53.8%　TOC),　which　likely　contributed　to　the　recalcitrant.　Nitrosomonas　and　Candidatus　Brocadia　were　the　major　AOB　and　anammox　bacteria　in　the　PN　and　anammox　reactors　respectively.　With　the　increased　THP-AD　centrate　proportion　in　the　feed,　the　abundance　of　both　population　declined.　Interestingly,　Denitratisoma,　being　the　major　denitrifying　bacteria　in　anammox　reactor,　had　relatively　stable　abundance　(7.0-7.9%)　when　THP-AD　centrate　was　improved　from　3　and　100%,　suggesting　the　inhibition　on　anammox　bacteria　was　not　due　to　the　overgrowth　of　denitrifying　microorganism　despite　the　high　organics　loading　rate.　Overall,　this　study　provides　a　guide　to　develop　the　energy-saving　PN/A　process　for　THP-AD　centrate　treatment　by　pointing　out　potential　challenges　and　mitigating　strategies.