The　double　circular　arc　spiral　bevel　gear　has　complex　tooth　surface,　and　its　design　process　is　very　tedious.　When　in　the　3D　modeling　process,　the　tooth　surface　of　double　circular　arc　spiral　bevel　gear　could　not　be　formed　simply　by　sweeping　the　tooth　profile　like　the　cylindrical　gears,　but　is　generated　according　to　the　equation　of　tooth　surface.　The　main　purpose　of　this　paper　is　to　achieve　automatic　modeling　and　assembly　of　nutation　reducer　through　the　development　of　parametric　design　system　for　double　circular　arc　spiral　bevel　gear　nutation　drive.　This　paper　utilizes　the　programming　language　VB.NET　to　call　the　SolidWorks　API　functions　in　the　Visual　Studio　integrated　development　environment,　takes　the　double　circular　arc　spiral　bevel　gears　as　main　modeling　object　and　combines　its　tooth　surface　equation　to　develop　the　parametric　design　system.　The　system　includes　3D　modeling　module　and　assembly　module.　In　the　3D　modeling　module,　it　can　realize　automatic　modeling　of　each　part　of　the　nutation　reducer;　in　the　assembly　module,　it　can　realize　the　whole　parts　assembly　of　the　reducer.　The　developed　parametric　design　system　enables　rapid　modeling　of　double　circular　arc　spiral　bevel　gears　with　complex　tooth　structure,　which　shortens　design　cycle　and　improves　design　quality　and　efficiency　of　the　nutation　reducer.　By　combining　structural　design　method　of　double　circular　arc　spiral　bevel　gear　nutation　reducer　with　SolidWorks　secondary　development　technology,　the　problem　of　tedious　reducer　design　is　solved,　which　can　contribute　the　promotion　and　application　of　double　circular　arc　spiral　bevel　gear　nutation　reducer.　©　2022,　The　Author(s),　under　exclusive　license　to　Springer　Nature　Singapore　Pte　Ltd.