Analytic　hierarchy　process　(AHP)　has　some　obviously　limitations　because　pairwise　comparison　process　is　complicated　and　meets　the　consistency　hard　with　the　increasing　in　the　number　of　factors,　which　weaken　the　applicability　of　AHP　a　lot.　In　order　to　overcome　these　limitations,　authors　introduced　gray　correlation　model　and　combined　the　two　methods　with　scales　of　transformation　conversion　of　gray　correlation　coefficient　matrix　and　abandoning　pairwise　comparison,　then　proposed　an　improved　analytic　hierarchy　process　(IAHP).　The　proposed　IAHP　overcomes　the　shortcomings　of　AHP　and　increases　the　applicability　of　AHP.　Based　on　the　IAHP,　a　comprehensive　evaluation　system　for　Langfang　Suning　plaza　foundation　engineering　was　set　up,　and　the　risks　of　the　excavation　process　were　assessed.　Finally,　extreme　high　degree　risks　were　determined　via　quantities　of　the　combination　weight,　which　will　provide　technical　guidance　for　engineering　construction　smoothly.　©　2018,　Editorial　Department　of　Journal　of　Beijing　University　of　Technology.　All　right　reserved.