The　calcareous　sand　foundation　may　be　liquefied　to　cause　structural　damages　under　dynamic　loadings　such　as　earthquakes　and　waves.　The　microbially　induced　calcite　precipitation(MICP)　can　enhance　the　strength　of　the　calcareous　sand　foundation　on　a　large　scale　and　improve　its　liquefaction　resistance.　In　this　paper,　the　dynamic　pore　pressure　development　of　MICP-treated　calcareous　sand　was　studied　through　a　series　of　cyclic　triaxial　tests,　and　the　effects　of　the　effective　confining　pressure,　the　dynamic　stress　ratio,　the　relative　density　and　the　biocementation　level　on　the　development　of　the　dynamic　pore　water　pressure　of　MICP-treated　calcareous　sand　were　investigated.　It　is　found　that　the　pore　water　pressure　development　of　MICP-treated　calcareous　sand　is　greatly　affected　by　the　dynamic　stress　ratio　and　the　biocementation　level.　Based　on　the　dynamic　stress　ratio　and　the　biocementation　level,　MICP-treated　calcareous　sand　presents　three　different　pore　water　pressure　development　patterns.　The　pore　water　pressure　curve　gradually　transitions　from　S-type　to　hyperbolic　type　with　increasing　the　dynamic　stress　ratio　or　the　biocementation　level.　Based　on　the　development　of　the　dynamic　pore　water　pressure,　an　uniform　pore　water　pressure　model　was　proposed　for　MICP-treated　calcareous　sand.　The　advantage　of　this　model　over　other　models　in　predicting　the　development　of　the　dynamic　pore　water　pressure　in　MICP-treated　calcareous　sand　was　demonstrated　through　comparisons.　©　2021,　Science　Press.　All　right　reserved.