Five　blended　yarns　were　spun　with　polyacrylonitrile　(PAN)　fibers　and　polypropylene　(PP)　fibers　at　different　blending　ratios,　and　then　knitted　into　fabrics.　The　obtained　blended　yarns　or　knitted　fabrics　were　modified　using　successive　amidoximation　and　coordination　with　Fe3+　ions　to　prepare　the　Fe-modified　PAN/PP　blended　yarns　or　knitted　fabrics.　They　were　used　as　the　heterogeneous　Fenton　catalysts　for　the　degradation　of　a　typical　azo　dye,　Reactive　Red　195,　to　investigate　the　effect　of　fiber　blending　ratio　on　the　modification,　as　well　as　mechanic　and　catalytic　performance.　The　results　indicated　that　increasing　PP　fiber　content　led　to　a　linear　increase　in　the　conversion　degree　of　cyano　groups　to　amidoxime　groups　and　Fe　content　fixed　on　the　surface　of　PAN　fibers　in　the　blend　yarn　or　fabric.　PP　fibers　showed　a　significant　effect　on　the　breaking　strength　and　elongation　at　break　of　the　blended　yarn,　and　a　critical　PP　fiber　content　was　found　to　obtain　minimum　values　for　strength　and　elongation.　This　is　due　mainly　to　a　large　difference　in　extensibility　between　the　two　fibers.　The　strength　and　elongation　of　the　obtained　knitted　fabric　were　greatly　improved　by　the　addition　of　PP　fibers.　On　the　other　hand,　the　blended　yarns　and　knitted　fabrics　with　higher　PP　fiber　content　exhibited　comparatively　stronger　catalytic　activity.　©　The　Author(s)　2013.