There　are　two　groups　of　tests　on　shrinkage　of　UHPC　under　the　sealed　and　un-sealed　conditions　in　this　paper,　the　effects　of　steel　fiber　content　and　fly　ash　on　autogenous　shrinkage　of　UHPC　was　studied.　In　addition,　a　more　rational　assembly　method　for　dial　gauge　was　proposed　and　employed,　which　improves　measurement　precision.　Test　results　show　that　the　shrinkage　of　UHPC　rapidly　grows　at　early　age,　70%-90%　shrinkage　was　measured　in　the　first　14　days　after　placing.　Fly　ash　attributes　large　influence　to　shrinkage　of　sealed　UHPC　while　steel　fiber　volume　has　a　relatively　small　effect　to　it;　the　incorporation　of　fly　ash　could　result　in　a　＂hysteresis　effect.＂　Based　on　the　test　results,　a　realistic　(autogenous)　shrinkage　model　of　sealed　UHPC　has　been　presented.