In　order　to　solve　the　problems　in　the　accuracy　and　adaptability　of　the　existing　methods　for　blade　twist　measurement,　a　high-precision　and　form-free　metrological　method　of　blade　twist　based　on　the　parameter　evaluation　of　twist　angular　position　and　twist　angle　is　proposed　in　the　study,　and　the　theoretical　model,　the　measurement　principle　and　the　key　technologies　of　the　method　are　discussed　in　detail.　Three　key　issues　of　the　twist　metrology　of　a　blade　are　solved　based　on　technologies　of　calibration,　a　priori　planning　and　geometric　analysis:　aeroengine　axis　matching,　high-precision　coordinate　acquisition　of　the　leading　edge　and　the　trailing　edge,　and　extraction　of　twist　angular　position　of　the　profile.　The　measurement　path　planning,　sampling　strategy　optimization　and　high-precision　coordinate　collection　are　executed　automatically　without　theoretical　model　data　of　the　measured　blade,　thus　the　form-free　and　high-precision　metrology　of　the　blade　twist　is　achieved.　The　research　results　show　that　the　metrological　method　of　blade　twist　presented　in　this　study　is　effective,　and　that　its　measurement　uncertainty　is　less　than　0.01ffi.　This　method　is　form-free,　efficient　and　accurate,　and　can　solve　the　problems　of　high-precision　measurement　and　evaluation　for　the　twist　of　aeroengine　blade　primely.　©　2020　by　the　authors.