Dialkyldimethyl　ammonium　compound　(DADMAC)　is　widely　used　in　daily　life　as　a　typical　disinfectant　and　often　co-exists　with　the　heavy　metal　zinc　in　sewage　environments.　This　study　investigated　the　effects　of　co-exposure　to　zinc　(1　mg/L)　and　DADMAC　(0.2-5　mg/L)　on　the　performance,　bacterial　community,　and　resistance　genes　(RGs)　in　a　partial　sulfur　autotrophic　denitrification　coupled　with　anaerobic　ammonium　oxidation　(PSAD-Anammox)　system　in　a　sequencing　batch　moving　bed　biofilm　reactor　for　150　days.　Co-exposure　to　zinc　and　low　concentration　(0.2　mg/L)　DADMAC　did　not　affect　the　nitrogen　removal　ability　of　the　PASD-Anammox　system,　but　increased　the　abundance　and　transmission　risk　of　free　RGs　in　water.　Co-exposure　to　zinc　and　medium-to-high　(2-5　mg/L)　DADMAC　led　to　fluctuations　in　and　inhibition　of　nitrogen　removal,　which　might　be　related　to　the　enrichment　of　heterotrophic　denitrifying　bacteria　dominated　by　Denitratisoma.　Co-exposure　to　zinc　and　high　concentration　DADMAC　(5　mg/L)　stimulated　the　secretion　of　extracellular　polymeric　substances　and　increased　the　proliferation　risk　of　intracellular　RGs　in　sludge.　This　study　provided　insights　into　the　application　of　PSADAnammox　system　and　the　ecological　risks　of　wastewater　containing　zinc　and　DADMAC.