A　modified　multi-component　solute　diffusion　equation　described　with　diffusion　flux　was　derived　in　detail　based　on　the　classical　Maxwell-Stefan　diffusion　theory.　The　friction　between　the　solute　species　and　the　soil　skeleton　wall,　which　is　proportional　to　the　relative　velocity　between　the　solute　species　and　the　soil　skeleton,　is　introduced.　The　chemical　potential　gradient　is　considered　the　driving　force.　A　one-dimensional　model　for　transport　of　multi-component　solute　in　saturated　soil　was　developed　based　on　the　modified　diffusion　equation　and　the　modified　competitive　Langmuir　adsorption　equation.　Numerical　calculation　of　a　case　of　two　heavy　metal　ion　species,　which　was　chosen　as　an　example,　was　carried　out　using　the　finite　element　software　COMSOL　Multiphysics.　A　comparative　analysis　was　performed　between　the　multi-component　solute　transport　model　developed　in　this　study　and　the　convection-diffusion　transport　model　of　single-component　solute　based　on　Fick＇s　law.　Simulation　results　show　that　the　transport　behavior　of　each　species　in　a　multi-component　solute　system　is　different　from　that　in　a　single-component　system,　and　the　friction　characteristics　considered　in　the　developed　model　contribute　to　obstructing　the　movement　of　each　solute　component.　At　the　same　time,　the　influence　of　modified　competitive　Langmuir　adsorption　on　solute　transport　was　investigated.　These　research　results　can　provide　strong　theoretical　support　for　the　design　of　antifouling　barriers　in　landfills　and　the　maintenance　of　operation　stability.　©　2018　Hohai　University