In　this　paper,　we　consider　the　large　time　behavior　of　planar　shock　wave　for　3D　compressible　isentropic　Navier-Stokes　equations　(CNS)　in　half　space.　Providing　the　strength　of　the　shock　wave　and　initial　perturbations　are　small,　we　proved　the　planar　shock　wave　for　3D　CNS　is　nonlinearly　stable　in　half　space　with　Navier　boundary　condition.　The　main　difficulty　comes　from　the　compressibility　of　shock　wave,　which　leads　to　lower　order　terms　with　bad　sign,　see　the　third　line　in　(4.36).　We　apply　a　decomposition　of　the　solution　into　zero　and　non-zero　modes:　we　take　the　anti-derivative　for　the　zero　mode　and　obtain　the　space-time　estimates　for　the　energy　of　perturbation　itself.　Then　combining　the　fact　that　the　Poincar　&　eacute;　inequality　is　available　for　the　non-zero　mode,　we　have　successfully　controlled　the　lower　order　terms　with　bad　sign　in　(4.36).　To　overcome　the　difficulty　that　comes　from　the　boundary,　we　introduce　the　two　crucial　estimates　on　boundary　lemma　(4.2)　and　fully　utilize　the　property　of　Navier　boundary　conditions,　which　means　that　the　normal　velocity　is　zero　on　the　boundary　and　the　fluid　tangential　velocity　is　proportional　to　the　tangential　component　of　the　viscous　stress　tensor　on　the　boundary.　Finally,　the　nonlinear　stability　is　proved　by　the　weighted　energy　method.