A　mixture　of　phenol,　acetic　acid,　and　naphthalene　was　partially　oxidized　in　supercritical　water　in　order　to　produce　hydrogen.　The　effects　of　temperature,　oxidation　ratio　(OR),　reaction　time,　and　reactant　concentrations　on　gaseous　distributions,　gasification　efficiencies,　and　reactants　removal　efficiencies　were　investigated.　Furthermore,　the　effects　of　oxygen　on　the　main　intermediate　products　were　analyzed,　and　possible　degradation　pathways　were　proposed.　Results　indicated　that　higher　temperatures　significantly　promoted　the　H-2　yield.　In　addition,　small　amounts　of　oxygen　(OR　＜0.2)　accelerated　the　production　of　H-2　and　CH4.　The　maximum　H-2　gasification　efficiency　(240.25%)　and　H-2　yield　(70.16　mmol　g(-1))　were　obtained　at　560　degrees　C,　25　MPa,　reaction　time　of　20　s　and　OR　of　0.2.　Longer　reaction　time　enhanced　the　gasification　efficiencies　in　10　s,　while　the　effect　was　little　when　reaction　times　longer　than　10　s.　The　concentrations　of　the　reactants　did　not　significantly　influence　the　gasification　efficiencies.　Copyright　(C)　2015,　Hydrogen　Energy　Publications,　LLC.　Published　by　Elsevier　Ltd.　All　rights　reserved.