In　order　to　reveal　the　oxidation　and　spontaneous　combustion　process　of　the　sulfur　corrosion　products　in　the　oil　storage　tanks,　the　thermal　decomposition　characteristics　of　FeS　and　FeS2　as　well　as　the　FeS-FeS2　compounds　of　the　main　products　of　sulfur　corrosion　products　in　storage　tanks　were　characterized　by　a　synchronous　thermal　analyzer　under　the　experimental　conditions　of　temperature　from　30　to　1000　and　at　heating　rates　of　10,　15　and　20/min.　The　TG-DTG-DSC　curves　of　FeS　and　FeS2　and　the　TG-DTG　curves　of　FeS-FeS2　compounds　were　compared　at　the　heating　rate　of　15/min.　Furthermore,　the　apparent　activation　energies　of　the　FeS-FeS2　compounds　were　determined　by　the　Flynn-Wall-Ozawa　(FWO)　method　and　the　Kissinger　method　of　thermal　analysis　kinetics,　respectively.　The　results　showed　that　the　ignition　temperature　of　the　six　samples　was　mainly　in　the　range　of　413.82-508.80.　Except　the　FeS,　the　TG　curves　of　the　other　samples　are　similar.　The　DTG　curves　have　two　mass　loss　peaks　in　the　temperature　range　of　500-650.　In　the　process　of　oxidation　and　spontaneous　combustion　of　FeS-FeS2　compounds,　FeS　and　FeS2　didn＇t　react　in　an　isolated　way,　but　interact　with　each　other.　When　the　mass　fraction　of　FeS2　was　20%,　the　average　apparent　activation　energy　was　the　lowest,　and　the　average　apparent　activation　energies　calculated　by　FWO　and　Kissinger　were　172.95　and　164.56　kJ/mol,　respectively;　consequently,　it　is　the　most　liable　to　spontaneous　combustion.　©　2017,　Editorial　Office　of　Acta　Petrolei　Sinica(Petroleum　Processing　Section).　All　right　reserved.