Enzyme-induced　carbonate　precipitation　(EICP)　is　an　emerging　and　environment-friendly　geotechnical　technique　for　soil　improvement.　Despite　the　extensive　amount　of　previous　studies　focusing　on　the　mechanical　properties　of　biocemented　samples　with　varying　calcium　carbonate　content,　less　is　known　about　the　cementitious　property　of　calcium　carbonate　crystals　generated　in　the　EICP　process.　This　paper　presents　a　systematic　study　on　the　effect　of　cementation　solution　concentration　(CCS)　on　cementitious　property　of　calcium　carbonate　crystals.　Solution　tests　were　conducted　to　ascertain　the　dominant　factor　causing　the　retarding　effect　of　CCS.　Glass　slide　tests　and　ultrasonic　oscillation　tests　were　performed　to　evaluate　the　cementitious　property　of　calcium　carbonate　crystal.　The　results　of　solution　tests　indicated　that　the　higher　CCS　would　affect　calcium　carbonate　production　and　calcium　conversion　efficiency,　which　is　mainly　caused　by　the　concentration　of　CaCl2　rather　than　urea.　The　increase　in　CCS　will　cause　calcium　conversion　efficiency　to　decrease　significantly,　and　calcium　carbonate　production　will　also　decrease　once　CCS　exceeds　a　threshold　value.　The　higher　CCS　contributes　to　formation　of　larger　calcium　carbonate　crystals　and　has　little　effect　on　the　morphological　characteristics　of　the　crystal.　Glass　slide　tests　showed　that　mineral　composition　is　controlled　by　the　CCS　of　EICP　solution.　Increasing　the　CCS　results　in　the　increased　vaterite　content,　which　affects　the　cementitious　property　of　calcium　carbonate　crystal,　especially　for　CCS　is　higher　than　1.0 M.　The　results　are　expected　to　help　identify　the　retarding　effect　of　CCS　and　to　provide　a　reference　for　optimizing　the　cementitious　property　of　calcium　carbonate　crystals.