The　precision　reducer　is　the　core　component　of　the　robot,　and　its　transmission　accuracy　determines　the　motion　accuracy　of　the　robot.　The　testing　machine　for　precision　reducer　is　the　basic　equipment　for　testing　the　transmission　accuracy　of　precision　reducer.　However,　so　far,　there　is　no　systematic　research　on　the　accuracy　characteristics　of　testing　bench　for　transmission　accuracy.　Therefore,　the　verification　regulation　to　evaluate　the　accuracy　performance　of　such　testing　machine　is　still　a　gap.　This　leads　to　inaccurate　results　and　inconsistent　evaluation　in　the　accuracy　evaluation　of　the　precision　reducer　testing　machine.　In　order　to　accurately　evaluate　the　accuracy　performance　of　testing　machine　for　precision　reducer,　an　accuracy　evaluation　system　for　the　whole　life　cycle　of　testing　machine　is　constructed.　The　accuracy　performance　of　testing　machine　is　traced　back　to　three　aspects:　test　condition　stability,　measurement　chain　accuracy　and　frequency　domain　state.　The　corresponding　characteristic　quantities　are　defined　for　each　aspect,　and　a　rapid　extraction　method　of　characteristic　quantities　for　the　production　site　is　proposed.　The　relationship　between　the　characteristic　quantities　and　the　accuracy　of　testing　machine　is　established.　The　accuracy　failure　criterion　of　testing　machine　is　determined.　Based　on　the　comprehensive　performance　testing　machine　for　precision　reducer　developed　by　the　research　group,　the　test　practice　for　5　years　has　been　carried　out.　The　results　show　that　the　value　of　the　characteristic　quantity　is　consistent　with　the　actual　accuracy　of　testing　machine,　which　verifies　the　validity　and　reliability　of　the　whole　life　cycle　accuracy　evaluation　system　of　testing　machine.　©　2024　Chinese　Mechanical　Engineering　Society.　All　rights　reserved.