There　were　two　forces　that　promoted　the　development　of　gear　measurement　technology.　One　was　the　continuous　new　requirements　for　gear　measurement　put　forward　by　industrial　development,　and　the　other　was　the　penetration　of　continuously　improving　related　technologies　in　the　field　of　gear　measurement.　Since　the　21st　century,　the　convergence　of　these　two　forces　promoted　the　rapid　development　of　gear　measurement　technology.　Based　on　a　brief　review　of　the　evolution　of　gear　accuracy　theory　and　gear　measurement　technology　in　the　20th　century,　the　basic　framework　of　gear　generalized　accuracy　theory　was　put　forward.　The　gear　measurement　technology　during　the　last　20　years　was　systematically　summarized　from　the　aspects　of　gear　full-information　measurement　technology,　in-site　rapid　gear　sorting　and　detection　technology,　extreme　measurement　technology　for　extra-large　gears　and　micro　gears,　high-precision　gear　artifacts　and　traceability,　etc.　There　is　more　than　100　years　since　the　beginning　of　gear　precision　measurement,　and　it　is　currently　in　the　critical　stage　of　the　transition　from　the　3rd　generation　to　the　next-generation　of　gear　measurement.　The　overall　technical　concept　of　next-generation　of　gear　measurement　was　presented,　the　basic　theory　and　key　technical　problems　that　must　be　overcome　were　listed　for　realizing　the　next-generation　of　gear　measurement,　and　the　research　focus　and　scientific　issues　of　gear　measurement　in　the　next　10　years　were　prospected.　©　2022,　China　Mechanical　Engineering　Magazine　Office.　All　right　reserved.