Based　on　the　investigation　of　airplane　enterprises,　the　paper　defines　the　life　cycle　of　the　airplane＇s　assembly　line　in　a　reasonable　way.　It　takes　the　model　of　project　list　in　the　stage　of　bidding　to　make　it　more　actual.　Regarding　the　airplane＇s　assembly　line,　it　also　applies　the　equipments　life　cycle　management　theory　into　the　using　stage　so　that　we　can　control　the　using　cost　more　effectively.　The　paper　uses　the　Crystal　Ball　to　analyze　the　risk　factors　of　the　airplane＇s　assembly　line　and　improves　the　investment　budget＇s　accuracy.