The　explicit　numerical　algorithm　for　the　near-field　wave　motion　of　fluid-saturated　porous　media　in　time　domain　is　investigated　based　on　u-p　dynamic　formulation.　The　wave　motion　equations　are　decoupled,　and　dynamic　coupling　is　eliminated　by　the　diagonalization　of　the　mass　matrix　and　pore　fluid　compression　matrix.　Based　on　the　decoupled　wave　motion　equations,　the　central　difference　method　and　Newmark　constant　average　acceleration　method　are　adopted　for　the　solution　of　solid-phase　displacement　and　velocity,　respectively.　The　formulation　of　pore　fluid　pressure　is　derived　based　on　the　backward　difference　method.　Then　the　explicit　staggered　calculating　formulas　for　the　dynamic　response　of　fluid-saturated　porous　media　are　derived,　and　a　new　full　explicit　numerical　algorithm　for　the　near-field　wave　motion　of　fluid-saturated　porous　media　in　time　domain　is　developed.　The　rationality　of　matrix　diagonalization　in　the　algorithm　is　validated.　The　numerical　results　gained　by　the　proposed　algorithm　accord　well　with　the　corresponding　analytical　results.　This　indicates　the　accuracy　of　the　proposed　algorithm.　Combining　the　time　domain　numerical　calculation　method　proposed　with　the　transmission　artificial　boundary　method,　it　is　applied　to　the　near　field　wave　motion　problem　of　fluid-saturated　porous　media,　and　the　seismic　response　of　saturated　soil　site　is　calculated　and　studied.　The　numerical　results　of　the　seismic　response　of　saturated　soil　field　accord　with　the　elastic　wave　motion　theory.　This　indicates　the　applicability　of　the　developed　algorithm　to　the　near-field　wave　motion　problem　of　fluid-saturated　porous　media.　The　stability　characteristic　of　the　developed　algorithm　is　investigated　based　on　the　transfer　matrix　of　the　iterative　calculating　formulas　of　the　algorithm.　In　the　developed　algorithm,　all　the　variables　of　dynamic　response　are　calculated　in　an　iterative　pattern.　Thusly,　this　algorithm　has　the　basic　characteristic　of　the　full　explicit　numerical　algorithm　in　time　domain.　In　the　developed　algorithm,　all　the　components　of　the　dynamic　response　are　solved　by　recursive　and　iterative　modes,　which　avoids　solving　the　coupled　dynamic　equations.　This　developed　algorithm　has　high　computational　efficiency　and　is　an　effective　algorithm　for　solving　near-field　wave　motion　problems　in　fluid-saturated　porous　media　in　time　domain.　©　2020,　Engineering　Mechanics　Press.　All　right　reserved.