Biomass　burning　injects　many　different　gases　and　aerosols　into　the　atmosphere　that　could　have　a　harmful　effect　on　air　quality,　climate,　and　human　health.　In　this　study,　a　comprehensive　biomass　burning　emission　inventory　including　domestic　and　in-field　straw　burning,　firewood　burning,　livestock　excrement　burning,　and　forest　and　grassland　fires　is　presented,　which　was　developed　for　mainland　China　in　2012　based　on　county-level　activity　data,　satellite　data,　and　updated　source-specific　emission　factors　(EFs).　The　emission　inventory　within　a　1　x　1　km(2)　grid　was　generated　using　geographical　information　system　(GIS)　technology　according　to　source-based　spatial　surrogates.　A　range　of　key　information　related　to　emission　estimation　(e.g.　province-specific　proportion　of　domestic　and　in-field　straw　burning,　detailed　firewood　burning　quantities,　uneven　temporal　distribution　coefficient)　was　obtained　from　field　investigation,　systematic　combing　of　the　latest　research,　and　regression　analysis　of　statistical　data.　The　established　emission　inventory　includes　the　major　precursors　of　complex　pollution,　greenhouse　gases,　and　heavy　metal　released　from　biomass　burning.　The　results　show　that　the　emissions　of　SO2,　NO　x,　PM10,　PM2.5,　NMVOC,　NH3,　CO,　EC,　OC,　CO2,　CH4,　and　Hg　in　2012　are　336.8　Gg,　990.7　Gg,　3728.3　Gg,　3526.7　Gg,　3474.2　Gg,　401.2　Gg,　34　380.4　Gg,　369.7　Gg,　1189.5　Gg,　675　299.0　Gg,　2092.4　Gg,　and　4.12　Mg,　respectively.　Domestic　straw　burning,　in-field　straw　burning,　and　firewood　burning　are　identified　as　the　dominant　biomass　burning　sources.　The　largest　contributing　source　is　different　for　various　pollutants.　Domestic　straw　burning　is　the　largest　source　of　biomass　burning　emissions　for　all　the　pollutants　considered,　except　for　NH3,　EC　(firewood),　and　NO　x　(in-field　straw).　Corn,　rice,　and　wheat　represent　the　major　crop　straws.　The　combined　emission　of　these　three　straw　types　accounts　for　80%　of　the　total　straw-burned　emissions　for　each　specific　pollutant　mentioned　in　this　study.　As　for　the　straw　burning　emission　of　various　crops,　corn　straw　burning　has　the　largest　contribution　to　all　of　the　pollutants　considered,　except　for　CH4;　rice　straw　burning　has　highest　contribution　to　CH4　and　the　second　largest　contribution　to　other　pollutants,　except　for　SO2,　OC,　and　Hg;　wheat　straw　burning　is　the　second　largest　contributor　to　SO2,　OC,　and　Hg　and　the　third　largest　contributor　to　other　pollutants.　Heilongjiang,　Shandong,　and　Henan　provinces　located　in　the　north-eastern　and　central-southern　regions　of　China　have　higher　emissions　compared　to　other　provinces　in　China.　Gridded　emissions,　which　were　obtained　through　spatial　allocation　based　on　the　gridded　rural　population　and　fire　point　data　from　emission　inventories　at　county　resolution,　could　better　represent　the　actual　situation.　High　biomass　burning　emissions　are　concentrated　in　the　areas　with　more　agricultural　and　rural　activity.　The　months　of　April,　May,　June,　and　October　account　for　65%　of　emissions　from　in-field　crop　residue　burning,　while,　regarding　EC,　the　emissions　in　January,　February,　October,　November,　and　December　are　relatively　higher　than　other　months　due　to　biomass　domestic　burning　in　heating　season.　There　are　regional　differences　in　the　monthly　variations　of　emissions　due　to　the　diversity　of　main　planted　crops　and　climatic　conditions.　Furthermore,　PM2.　5　component　results　showed　that　OC,　Cl-,　EC,　K+,　NH4+,　elemental　K,　and　SO42-　are　the　main　PM2.5　species,　accounting　for　80%　of　the　total　emissions.　The　species　with　relatively　high　contribution　to　NMVOC　emission　include　ethylene,　propylene,　toluene,　mp-xylene,　and　ethyl　benzene,　which　are　key　species　for　the　formation　of　secondary　air　pollution.　The　detailed　biomass　burning　emission　inventory　developed　by　this　study　could　provide　useful　information　for　air-quality　modelling　and　could　support　the　development　of　appropriate　pollution-control　strategies.