The　development　of　high-performance　acetone　gas　sensor　is　of　great　significance　for　environmental　protection　and　personal　safety.　SnO　2　has　been　intensively　applied　in　chemical　sensing　areas,　because　of　its　low　cost,　high　mobility　of　electrons,　and　good　chemical　stability.　Herein,　we　incorporated　nitrogen　atoms　into　the　SnO　2　nanostructure　by　simple　solvothermal　and　subsequent　calcination　to　improve　gas　sensing　property　for　acetone.　The　crystallization,　morphology,　element　composition,　and　microstructure　of　as-prepared　products　were　characterized　by　X-ray　diffraction　(XRD),　transmission　electron　microscopy　(TEM),　scanning　electron　microscopy　(SEM),　X-ray　photoelectron　spectroscopy　(XPS),　Electron　paramagnetic　resonance　(EPR),　Raman　spectroscopy,　UV–visible　diffuse　reflectance　spectroscopy　(UV–vis　DRS),　and　the　Brunauer–Emmett–Teller　(BET)　method.　It　has　been　found　that　N-incorporating　resulted　in　decreased　crystallite　size,　reduced　band-gap　width,　increased　surface　oxygen　vacancies,　enlarged　surface　area,　and　narrowed　pore　size　distribution.　When　evaluated　as　gas　sensor,　nitrogen-incorporated　SnO　2　nanostructure　exhibited　excellent　sensitivity　for　acetone　gas　at　the　optimal　operating　temperature　of　300　◦　C　with　high　sensor　response　(R　air　/R　gas　−　1　=　357)　and　low　limit　of　detection　(7　ppb).　The　nitrogen-incorporated　SnO　2　gas　sensor　shows　a　good　selectivity　to　acetone　in　the　interfering　gases　of　benzene,　toluene,　ethylbenzene,　hydrogen,　and　methane.　Furthermore,　the　possible　gas-sensing　mechanism　of　N-incorporated　SnO　2　toward　acetone　has　been　carefully　discussed.　©　2019　by　the　authors.　Licensee　MDPI,　Basel,　Switzerland.