Rapid　heating　of　coal　particles　in　supercritical　water　(SCW)　is　the　prerequisite　for　complete　gasification,　while　there　is　a　rapid　precipitation　of　volatiles　during　this　process.　If　the　volatiles　cannot　be　dissolved　and　diffused　in　time,　side　reaction　is　inclined　to　occur,　especially　coking.　The　solubility　of　the　volatiles　in　SCW　has　not　yet　been　studied　because　the　composition　is　not　simple　and　the　corresponding　interaction　with　SCW　is　complex.　In　this　paper,　polycyclic　aromatic　hydrocarbons　(PAHs)　were　used　as　the　volatile　model　compound.　Molecular　dynamics　(MD)　simulations　focused　on　the　dissolution　of　pure　PAHs　and　PAHs　mixtures　in　SCW　were　carried　out.　The　investigation　results　indicated　that　the　dissolution　behavior　of　naphthalene　was　the　most　excellent　in　SCW,　while　heavy　PAHs　were　sensitive　to　the　thermodynamic　state　of　water　molecules.　The　light　PAHs　were　liable　to　be　dissolved,　while　heavy　PAHs　were　more　likely　to　be　remained　in　the　PAH　droplet.　Moreover,　the　increase　of　temperature　and　density　has　a　positive　impact　on　the　dissolution　of　PAHs　in　the　supercritical　solvent.　This　work　is　prospective　to　provide　a　theoretical　basis　for　ensuring　efficient　and　complete　gasification　of　coal　and　restraining　side　effects　for　hydrogen　production.　©　2020　Hydrogen　Energy　Publications　LLC