Microstructure　and　mechanical　properties　of　as-cast　FCC　Al0.3CoCrFeNi　high-entropy　alloy　after　rolling　and　subsequent　annealing　were　investigated　by　means　of　XRD,　SEM,　EBSD,　TEM　and　tensile　test.　The　results　show　that　after　rolling　and　subsequent　annealing　at　600-1000℃,　recrystallization　occurs　and　AlNi-rich　ordered　BCC　phases　preferentially　precipitate　at　FCC　grain　boundaries.　With　annealing　temperature　increasing,　the　volume　fraction　of　precipitations　first　increases　and　then　decreases.　This　alloy　can　be　dramatically　strengthened　by　rolling　and　can　be　further　hardened　without　sacrificing　uniform　ductility　by　subsequent　annealing　at　600℃,　while　a　decrease　of　strength　and　an　increase　of　ductility　appear　after　further　increasing　annealing　temperature.　Specially,　after　rolling　and　annealing　at　800℃,　the　alloy　exhibits　optimal　mechanical　performance　with　uniform　elongation　of　34.1%　and　ultimate　tensile　strength　of　935　MPa,　which　is　three　times　than　that　of　the　as-cast.　This　is　ascribed　to　refined　microstructure　and　precipitation　hardening.　©　2015,　Editorial　Office　of　Transactions　of　Materials　and　Heat　Treatment.　All　right　reserved.