The　chemical　element　composition　of　dust　particles　was　characterized　by　the　ground-based　samples　collected　at　Beijing　in　the　spring　of　2004.　Most　of　mineral　and　pollutant　element　concentrations　in　particles　were　elevated　in　dusty　days,　about　2-4　times　higher　than　the　levels　in　non-dusty　days.　Each　of　Si,　Ca,　Fe　and　Al　accounted　for　over　10%　of　the　sums　of　total　20　elements　in　mass,　for　example,　Si　was　in　44.3%,　38.7%　for　dusty　and　non-dusty　cases,　respectively.　Si,　Fe,　Ni　or　Ti　can　be　used　as　an　indicator　of　dust　outflow,　and　Cu　can　be　viewed　as　an　evidence　of　dust　particles　mixing　with　anthropogenic　contaminants　as　a　result　of　coagulation　processes.　Mineral　and　pollutant　elements　showed　a　bimodal　distribution　in　the　mass　particle-size　distributions　in　both　dusty　and　non-dusty　days,　but　their　peak　concentrations　fell　in　different　size　stages.　Zn,　Cl　and　Cu　were　mostly　enriched　in　fine　particles,　Pb　was　enriched　in　intermediate　sized　particles,　but　most　mineral　elements,　S　and　part　of　Cu　were　enriched　in　coarse　particles.　Mineral　elements　were　dominated　by　crustal　material,　and　pollutant　elements　were　from　non-crustal　material　including　local　and　remote　sources.　Among　the　crustal　material,　part　of　Ca　was　originated　from　local　construction　activities.　High　concentration　of　Cu　was　related　to　the　of　rapidly　increasing　vehicles　in　Beijing,　and　the　replacing　of　coal　with　diesel　oil　for　heating　fuel.　Most　of　the　mineral　dust　particles　sampled　at　Beijing　were　originated　from　the　Mongolian　sandy　soil　and　the　Chinese　loess　in　the　spring　of　2004.　Using　Mg/Al　ratio　element　tracer　technique　method,　the　aerosol　from　outside　Beijing　accounted　for　66.3%　and　88.6%　to　the　total　mineral　aerosol　during　dust　event　on　10-11　March　and　28-30　March　2004,　respectively.