In　order　to　improve　the　effect　of　path　planning　in　emergencies,　the　missing　position　imputation　and　velocity　restoration　in　vehicle　trajectory　provide　data　support　for　emergency　path　planning　and　analysis.　At　present,　there　are　many　methods　to　fill　in　the　missing　trajectory　information,　but　they　basically　restore　the　missing　trajectory　after　analyzing　a　large　number　of　datasets.　However,　the　trajectory　reduction　method　with　few　training　sets　needs　to　be　further　explored.　For　this　purpose,　a　novel　trajectory　data　cube　model　(TDC)　is　designed　to　store　time,　position,　and　velocity　information　hierarchically　in　the　trajectory　data.　Based　on　this　model,　three　trajectory　Hierarchical　Trace-Back　algorithms　HTB-p,　HTB-v,　and　HTB-KF　are　proposed　in　this　paper.　Finally,　experiments　verify　that　conduct　in　a　different　number　of　sample　sets,　it　has　a　satisfactory　performance　on　information　restoration　of　individual　points　of　the　trajectory　and　information　restoration　of　trajectory　segments.