Assessing　the　adsorption　competition　between　arsenate　(As(V))　and　phosphate　(P(V))　is　crucial　due　to　their　coexistence　in　water.　This　paper　studied　the　competitive　adsorption　processes　of　As(V)　and　P(V)　on　magnetic　iron-based　alginate-chitosan　beads　by　beaker　experiments,　simultaneously　using　XRD　and　FTIR　techniques　for　characterization.　In　the　single　system,　both　As(V)　and　P(V)　adsorption　on　M-IACBs　followed　the　Langmuir　model,　with　maximum　adsorption　capacities　of　14.2　±　0.4　mg　g−1　and　18.5　±　0.4　mg　g−1,　respectively.　In　the　binary　system,　the　competitive　adsorption　of　As(V)　and　P(V)　is　a　multilevel　heterogeneous　process　well　evaluated　by　the　extended　Freundlich　and　pseudo-second-order　models.　When　loaded　simultaneously,　the　adsorption　of　As(V)　was　more　significant　than　that　of　P(V)　(2.72　mg　g−1　vs.　1.71　mg　g−1).　The　desorption　of　P(V)　was　favored　over　As(V)　during　sequential　loading,　and　the　adsorption　of　P(V)　was　more　influenced　by　pH　compared　to　As(V).　The　adsorption　affinity　of　the　composites　follows　the　order:　As(V)　＜　P(V)　(for　the　single　system)　and　As(V)　＞　P(V)　(for　the　binary　system).　Finally,　changes　in　arsenic　species　were　studied　under　anoxic　aqueous　solutions　and　oxygen-enriched　air.　In　aqueous　solutions,　As(V)　is　reduced　to　the　more　toxic　and　mobile　As(III)　by　Fe(II),　and　As(III)　exhibits　desorption-readsorption　behavior.　In　oxygen-enriched　air,　As(V)　undergoes　electron　transfer　with　Fe(II)　and　O2,　resulting　in　the　appearance　of　As(III),　which　can　also　be　oxidized　back　to　As(V).　This　study　provides　an　objective　and　critical　evaluation　of　the　data　regarding　the　use　of　Fe-based　adsorbents　in　removing　As(V),　offering　novel　insights　for　designing　such　adsorbents.　©　2023　Elsevier　B.V.