Se-based　cathodes　have　caught　tremendous　attention　owing　to　their　comparable　volumetric　capacity　and　better　electronic　conductivity　to　S　cathodes.　However,　its　low　utilization　ratio　and　sluggish　redox　kinetics　due　to　the　high　reaction　barrier　of　solid-phase　transformation　from　Se　to　Li2Se　limit　its　practical　application.　Herein,　an　insitu　texturing　hollow　carbon　host　by　gas-solid　interface　reaction　anchored　with　Fe　single-atomic　catalyst　is　designed　and　prepared　for　advanced　Li-Se　batteries.　This　Se　host　presents　high　pore　volume　of　1.49　cm3　g-1,　Fe　single　atom　content　of　1.53　wt%,　and　its　specific　structure　protects　single-atomic　catalyst　from　the　destructive　reaction　environment,　thus　balancing　catalytic　activity　and　durability.　After　Se　loading　by　reduction　of　H2SeO3,　this　homogenous　Se-based　cathode　delivers　a　superior　rate　capacity　of　431.3　mA　h　g-1　at　4C,　and　great　discharge　capacity　of　301.8　mA　h　g-1　after　1000　cycles　at　10C,　with　high　Li-ion　diffusion　coefficient　and　capacitancecontributed　ratio.　The　distribution　of　relaxation　times　analysis　verifies　solid-phase　transformation　mechanism　of　this　cathode　and　density　functional　theory　calculations　confirm　the　adsorption　and　bidirectionally　catalysis