In　this　paper,　the　morphology　of　turbulent　diffusion　flames　with　varying　aspect　ratios　under　slope　conditions　was　investigated.　A　simulated　fire　source　using　propane　gas　with　an　area　of　80　cm2　was　utilized.　The　influences　of　slope　angle　and　aspect　ratio　of　the　fire　source　on　the　flame　tilt　angle　(between　the　plume　centerline　and　the　slope),　flame　length,　and　flame　height　were　systematically　studied.　The　aspect　ratio　of　the　fire　source　(L/W)　was　changed　from　1　to　8,　and　the　slope　angle　was　changed　from　0°　to　40°.　Results　indicate　that　the　presence　of　a　slope　causes　asymmetrical　air　entrainment　on　both　sides　of　the　fire　plume,　causing　a　pressure　difference　that　leads　to　a　decrease　in　the　flame　tilt　angle　as　the　slope　angle　increases.　Additionally,　the　flame　length　increases　monotonically　with　the　slope　angle　due　to　the　enhanced　component　of　thermal　buoyancy　along　the　slope.　Under　the　same　slope　condition,　the　flame　tilt　angle　and　flame　height　(perpendicular　to　the　slope)　decrease　as　the　aspect　ratio　increases.　This　phenomenon　is　attributed　to　the　increased　entrainment　restriction　effect　of　the　slope　on　the　fire　plume.　New　models　for　calculating　flame　tilt　angle,　flame　length,　and　flame　height,　which　consider　the　slope　angle　and　aspect　ratio　of　the　fire　source　were　established　by　using　the　equivalent　perimeter　of　plume　entrainment.　To　further　verify　the　reliability　of　the　newly　established　models,　reference　data　with　wide　heat　release　rate　(6.15　kW–231　kW),　different　slope　inclination　angle　(0°–80°),　pool　size　(equivalent　diameter:　9　cm–44.1　cm),　and　different　fuels　(propane,　ethylene)　were　used　to　against　with　the　predicted　values　of　our　correlations.　It　is　found　that　the　maximum　error　of　all　correlations　is　within　15–20%,　their　universality　and　accuracy　are　further　verified.　©　2023