An　accurate　absorbing　boundary　condition　(ABC)　is　proposed　to　incorporate　in　the　frequency-domain　finite　element　simulation　for　numerically　solving　u-U　elastic　wave　equations　in　horizontally　multilayer　fluid-saturated　porous　media.　The　u-U　elastic　wave　equations　are　first　discretized　only　along　the　depth　direction　in　which　the　material　properties　are　heterogeneous,　analytical　method　using　in　the　remaining　coordinate　direction.　A　general　eigenvalue　problem　on　the　horizontal　wavenumber　is　then　solved　with　the　frequency　as　known　parameter.　Dynamic　stiffness　on　the　artificial　boundary　of　finite　domain　is　finally　obtained　as　ABC　based　on　the　solution　to　the　above　eigenvalue　problem.　The　proposed　ABC　is　mathematically　derived　without　introducing　any　approximate　assumptions,　and　the　only　approximation　comes　from　the　finite-element　discretization　of　the　fluid-saturated　porous　medium　in　the　depth　direction.　The　proposed　ABC　can　also　be　coupled　seamlessly　with　the　finite　element　method　(FEM).　Numerical　examples　of　wave　radiation　problems　are　given　to　demonstrate　the　effectiveness　of　the　proposed　ABC　and　its　coupling　with　FEM.　Finally,　a　practical　application　of　proposed　ABC　to　assess　the　topography　effects　of　the　fluid-saturated　porous　basin-type　site　is　presented　to　show　that　the　proposed　ABC　can　also　be　used　to　solve　wave　scattering　problems　in　geotechnical　earthquake　engineering.