Low-density　multi-principal　element　alloys　(MPEAs)　combining　a　high　specific　strength　and　considerable　ductility　have　remained　a　research　hotspot,　due　to　their　promising　prospects　for　energysaving　industrial　applications.　Light　Ti-containing　AlNbZrTix　(x　=　1−3)　MPEAs　were　designed　and　prepared　by　induction　melting　and　annealing.　As　the　Ti　content　increases,　the　microstructure　of　these　MPEAs　evolves　from　dual　phase　(B2-ordered　and　Zr5Al3-type　structure)　into　a　singlephase　B2-ordered　structure,　while　the　density　reduces　by　~8.7%,　from　~5.85　g·cm−3　(x　=　1)　to　~5.34　g·cm−3　(x　=　3).　Unexpectedly,　the　AlNbZrTix　(x　=　1,　2,　3)　alloys　possess　high　specific　yield　strengths　of　~270　kPa·m3·kg−1,　~221　kPa·m3·kg−1,　>208　kPa·m3·kg−1,　along　with　excellent　fracture　strains　of　~17.8%,　21.8%,　and　>50%,　respectively.　These　combined　compressive　properties　are　superior　to　the　reported　data　of　most　BCC/B2-dominant　MPEAs.　The　deformation　mechanism　of　the　B2ordered　structure　is　explained　as　a　dislocation-based　mechanism,　accompanied　by　antiphase　domains.　Here,　the　effect　of　Ti　on　the　microstructure　and　compressive　properties　of　AlNbZrTix　MPEAs　was　investigated,　providing　scientific　support　for　the　development　of　advanced　low-density　materials.　©　2022　by　the　authors.　Licensee　MDPI,　Basel,　Switzerland.