In　this　paper,　Ti-5Al-2.5Sn　ELI　alpha　titanium　alloy　was　prepared　by　laser　powder　bed　fusion.　The　effects　of　heat　treatment　and　HIP　process　on　the　densification　behavior,　microstructure　evolution,　low-temperature　me-chanical　properties,　and　fracture　behavior　of　Ti-5Al-2.5Sn　ELI　titanium　alloy　were　analyzed.　The　experi-mental　results　show　that　the　density　of　Ti-5Al-2.5Sn　ELI　titanium　alloy　is　improved　after　HIP　treatment.　Complete　recrystallization　occurred　in　the　deposited　microstructure,　and　the　recrystallized　alpha　grains　coar-sened　with　the　increase　in　holding　time.　After　heat　treatment,　the　tensile　strength　decreases　gradually,　while　the　elongation　increases　with　the　increase　of　holding　time.　Compared　with　300　K,　the　ultimate　tensile　strength　and　yield　strength　of　the　sample　at　77　K　were　improved,　but　the　elongation　decreased.　Ti-5Al-2.5Sn　ELI　titanium　alloy　annealed　at　850　degrees　C/4　h　exhibits　mixed　ductile-brittle　fracture　morphology　at　77　K　and　obtains　ultrahigh　strength　and　ductility.　At　the　same　time,　Ti-5Al-2.5Sn　ELI　titanium　alloy　exhibits　unit　slip　deformation　behavior　at　300　K,　while　at　77　K,　it　mainly　exhibits　the　coupling　of　dislocation　slip　and　twin　deformation　behavior.　These　findings　lay　a　foundation　for　the　rapid　preparation　of　high-strength　alpha-titanium　alloy　products　with　good　ductility.　(c)　2023　Elsevier　B.V.　All　rights　reserved.