Developing　efficient　technologies　to　recover　carbon　(C)　and　phosphorus　(P)　from　waste　activated　sludge　(WAS)　is　crucial　for　promoting　low-carbon　development　and　addressing　P　resource　shortages.　This　study　proposes　a　potassium　ferrate　(PF)　pretreatment　method　to　enhance　the　co-fermentation　of　WAS　and　corn　straw　(CS),　facilitating　the　efficient　and　stable　recovery　of　short-chain　fatty　acids　(SCFAs)　and　vivianite,　while　exploring　the　underlying　mechanisms　and　potential　applications　of　this　approach.　PF　pretreatment　effectively　promoted　WAS　hydrolysis　and　increased　CS　bioavailability.　SCFAs　yield　in　the　co-fermentation　group　reached　6410.4　mg/L,　representing　a　79.6　%　increase.　Efficient　SCFAs　production　was　achieved　under　a　SRT　of　4-5　days.　In　the　system,　SCFAs-consuming　bacteria　were　reduced　and　SCFAs-producing　fermentative　genera,　such　as　Paraclostridium,　Terrisporobacter　and　Mobilitalea,　were　enriched.　Additionally,　the　presence　of　Fe　promoted　the　enrichment　of　the　Clostridium　genus,　which　is　capable　of　both　fermentation　and　Fe　reduction.　PF　pretreatment　enhanced　the　release　of　organic　matter,　thereby　shortening　the　fermentation　time.　P　recovery　was　effectively　achieved　through　chemical　acidification　and　precipitation　techniques.　Under　optimal　recovery　conditions　(Fe/P　=　1.5,　pH　=　7,　300　rpm),　the　P　recovery　efficiency　reached　81.6　%,　with　vivianite　accounting　for　68.2　%-71.8　%.　This　method　provides　a　theoretical　foundation　and　technical　support　for　the　effective　utilization　of　WAS.