The　influence　of　simplex　aging　and　duplex　aging　on　the　microstructures　and　mechanical　properties　of　Ti-10V-2Fe-3Al　(Ti1023)　alloys　were　investigated.　Results　show　that　for　the　same　aging　time,　yield　strength　of　duplex　aged　samples　is　slightly　lower　than　that　of　simplex　aged　samples.　However,　elongation　of　duplex　aged　samples　is　significantly　higher　than　that　of　simplex　aged　ones.　Compared　with　the　simplex　aged　samples,　the　better　combination　of　strength　and　ductility　occurs　in　duplex　aged　ones.　SEM　fractography　of　simplex　aged　samples　shows　intergranular　fracture　mode　at　lower　magnification　but　grain　boundary　ductile　fracture　at　higher　magnification.　However,　for　duplex　aged　samples,　transgranular　dimple　fracture　is　dominant.　Microstructure　observations　show　that　the　good　combination　of　strength　and　ductility　of　duplex　aged　samples　is　attributed　to　the　microstructure　of　alternately　arranged　alpha/beta　plates,　the　suppression　of　continuous　grain　boundary　alpha　film　and　the　decreased　strength　difference　between　the　beta　aged　matrix　and　the　beta　grain　boundary　precipitate　zone.