Various　colloids　are　present　in　the　natural　groundwater　environment,　and　colloids　act　on　the　processes　involved　when　radionuclides　leak　from　a　repository　in　a　high-level　waste　disposal　site.　This　paper　investigates　the　effect　of　colloidal　silicate　in　natural　groundwater　environments　on　the　migration　behaviour　of　Sr(II).　Three　different　experimental　cases　have　been　designed:　(1)　effect　in　the　presence　of　colloidal　silicate,　(2)　effect　in　the　presence　of　a　porous　medium,　and　(3)　effect　in　the　presence　of　both　colloidal　silicate　and　porous　medium　(referred　to　as　CS,　PM,　and　PC,　respectively).　Batch　experiments　were　used　to　study　the　effect　of　influencing　factors　on　Sr(II)　migration　behaviour,　such　as　the　amount　of　CS,　solid-to-liquid　ratio,　pH,　contact　time,　and　initial　concentration　of　Sr(II).　The　experiments　showed　that　the　effect　of　PC　on　the　migration　behaviour　of　Sr(II)　was　greatest,　and　the　presence　of　CS　enhanced　the　sorption.　The　colloid　amount,　pH,　and　solid-to-liquid　ratio　significantly　affected　the　migration　behaviour.　The　more　the　colloids　were　added,　the　better　the　adsorption　effect.　The　optimal　pH　and　solid-to-liquid　ratio　were　6　and　20　:　1,　respectively.　The　alkaline　environment　is　more　conductive　to　colloid　sorption.　When　the　solid-to-liquid　ratio　was　20　:　1,　the　sorption　percentage　of　PC　is　0.5　times　larger　than　PM.　Although　the　PC　has　a　longer　adsorption　equilibrium　time,　the　percentage　of　adsorption　can　be　larger　than　that　in　the　other　two　cases.　The　kinetics　and　isotherms　of　Sr(II)　were　best　described　by　the　pseudo-second-order　and　Langmuir　models.　It　was　inferred　that　strong　chemical　interactions　and/or　surface　complexation　contributed　primarily　to　Sr(II)　sorption,　and　the　process　was　on　the　monolayer　adsorption　of　the　outer　surface.　These　findings　provide　valuable　information　for　the　migration　behaviour　of　strontium　in　groundwater　environments　of　geological　disposal　site.　At　the　same　time,　it　provides　information　for　the　implementation　of　permeable　reactive　barrier　technology　to　control　the　transport　of　radioactive　Sr(II)　and　its　species　in　natural　surface　and　groundwater.