The　aging　microstructures　and　properties　of　Ti-B20　alloy,　a　new　high　strength　metastable　beta　titanium　alloy　which　was　designed　according　to　the　principle　of　＇　critical　molybdenum　equivalence　and　multi-components　strengthening＇,　were　investigated　under　different　heat　treatment　conditions.　The　results　show　that　compared　to　traditional　metastable　β　titanium　alloys,　Ti-B20　alloy　has　more　rapid　aging　response,　much　higher　aging　strengthening　effect　and　much　finer　but　homogeneous　depositions.　After　α-β　solution　and　500-600°C　aging　treatment,　excellent　strength　and　plasticity　properties　can　be　achieved　(ultimate　tensile　strength:　1200-1500　MPa;　elongation;　8%-18%)　and　no　precipitate-free　regions　have　been　found　during　high　temperature　aging　treatment.　Beside,　the　aging　strength　of　alloy　after　solution　treatment　in　β　region　is　considerably　higher　than　that　in　α-β　region.　But　β　solution　and　aging　treatment　will　lead　to　remarkable　decrease　of　tensile　ductility.　All　these　aging　characteristics　of　T1-B20　alloy　are　responsible　for　its　specific　components.