As reported by different emission inventories in the Lombardy region and in the Po Valley, residential wood combustions (RWC) is a relevant source of inhalable primary aerosols in the size range smaller than 10 microns (PM10). The IN.EM.AR. emission inventory (www.inemar.eu) shows that in Lombardy, during 2008, the residential heating sector has determined 46% of PM10 total emissions of the region, and this amount was due for 99% to the combustion of biomass. The emissions from RWC have been assessed through a literature review of the emission factors for small biomass burning installations and from telephonic surveys that allowed to quantify the consumption of biomass in different type of small appliances as well as the temporal pattern of consumption. Source apportionment studies on the urban areas and wood burning tracers identification have also confirmed the importance of biomass burning as a source of PM10.