Chemical　oxidation　of　graphite　and　subsequent　exfoliation　allow　the　large-scale　production　of　isolated　graphene　oxide　(GO),　in　which　the　induced　oxygen-containing　functional　groups　on　GO　surface　were　then　removed　by　means　of　reduction　processes.　The　residual　functional　groups　including　carbonyl,　hydroxyl　and　epoxy　groups　as　well　as　the　newly　formed　defects,　significantly　influence　the　physical　properties　of　reduced　GO　(RGO).　Here,　RGO　structures　were　generated　through　a　thermal　reduction　process　of　GO　using　molecular　dynamics　simulations,　in　which　the　transformation　of　functional　groups　and　the　formation　of　non-hexagonal　rings/defects　were　captured.　The　results　suggested　the　formation　of　two　RGO　structures　with　different　contents　of　functional　groups　at　C/O　ratios　of　about　11　and　13.　These　structures　were　obtained　using　various　durations　of　the　thermal　reduction　process.　The　dependence　of　tensile　behaviour　of　RGOs　on　the　structure　and　chirality　as　well　as　the　influence　of　temperature　on　the　tensile　properties　of　RGOs　were　also　evaluated.　It　was　found　that　the　strength　and　Young＇s　modulus　of　RGOs　decreased　as　a　result　of　the　residual　functional　groups　and　newly　formed　defects,　and　were　decreased　with　the　environment　temperature.