The　capillary　effect　caused　by　the　confinement　in　porous　media　leads　to　strongly　differences　in　the　physical　properties　and　phase　equilibrium　of　the　fluids　apart　from　the　bulk　phase.　A　joint　model　was　established　for　investigating　the　capillary　effect　by　combining　Young-Laplace　equation　and　the　square-well　chain-like　fluid　with　variable　well-width　range　(SWCF-VR)　equation　of　state.　The　Young-Laplace　equation　supplies　a　simple　way　to　relate　the　capillarity　with　the　bulk　properties,　and　the　SWCF-VR　equation　was　able　to　accurately　describe　the　equilibrium　of　fluid　in　bulk　phase　compared　with　the　Peng–Robinson　equation.　The　model　could　predict　well　the　phase　equilibrium　when　comparing　with　experimental　data　in　bulk,　and　consequently　the　results　for　confined　fluids.　The　model　was　verified　by　experimental　and　computer　simulation　data.　Further,　the　binary　adjustable　parameters　of　SWCF-VR　EOS　used　in　this　study　could　be　updated　once　the　experimental　data　in　confined　situation　are　reported.　In　addition,　the　model　could　be　used　for　complex　component　when　experimental　data　are　unavailable　since　the　four　parameters　of　EOS　could　be　predicted.　©　2019　Elsevier　B.V.