Air aerosol samples for TSP (total suspended particulate) and coarse particulate (particle matter with aerodynamic diameter 2.5–10 μm, PM2.5–10) and metallic elements were collected during February 2008 to July 2008 in urban and peri-urban areas of Addis Ababa, Ethiopia. The seasonal variation mean concentration of TSP and PM10 were in the range of 17-556 μg/m3 and 27-285 μg/m3 respectively. The highest TSP and PM10 peak values were observed in February 2008 at Nefas Silk Lafto and Kotebe Waste Water Treatment Plant sites respectively. The lowest TSP and PM10 peak values were observed in June and July 2008 at Kality substation and COLTI sites respectively. The mean TSP concentration surpassed the WHO safe guideline value of 150 μg/m3 and 79 % of the PM10 values were below the WHO guideline value. The PM10 to TSP mass ratio was between (0.26 -0.59) and PM10 mass contributed ~39% to the TSP mass. The average element concentration order was Ca > Na > K > Zn > Sb >B > Al > V > Mg > S > Fe in PM10 filter sample. All the analyzed elements contributed ~0.1% to the PM10 mass. Crustal elements have strong correlation as do anthropogenic sources emissions which suggest the presence of similar sources. SEM-EDAX analysis of PM10 filter mass showed that Si, Al, Na, Zn, Ba, K and C were the predominant species. Crustal materials contributed 76-95% and C and Cu was from 5-24%. The size distribution of aerosol particles as derived from SEM analysis was in 0.43-9.3 μm range.