This　paper　explores　the　application　of　polar　codes　for　Walsh-code-based　multi-access　differentially　differential　chaos　shift　keying　(DDCSK-WC)　system.　As　such,　a　serial　concatenated　coding　of　the　channel　detector　and　the　polar　decoder　is　formed.　In　particular,　the　proposed　polar-coded　DDCSK-WC　system　does　not　require　the　channel　state　information,　which　avoids　complex　channel　estimation　and　simplifies　the　receiver　implementation　as　in　uncoded-DDCSK-WC　scheme.　Simulation　results　verify　that　the　performance　improvement　of　the　polar　coded　DDCSK-WC　system　over　uncoded　one　in　Rayleigh　multipath　fading　channels.　Besides,　the　performance　advantage　of　the　polarcoded　DDCSK-WC　is　illustrated　over　a　realistic　ultra-wideband　(UWB)　channel.　Therefore,　the　proposed　chaotic-based　polarcoded　scheme　offers　a　promising　aLTErnative　for　short-length　lowcost　and　low-complexity　communication,　such　as　wireless　local　area　network　applications.　©　2019　IEEE.