Physicochemical characterization of particulate matter fractionated into eight samples by size from 10 to 0.43 μm was performed by HS-SPME/GC-MS for the organic (semi-)volatile components and SEM X-ray microanalysis (SEM/EDX) for analysis of the elemental composition. The HS-SPME technique was shown to be efficient with respect to requiring an extremely low amount of material, being selective and clean and avoiding use of any solvents. Particulate matter was collected at four sites characterized by particular environmental locations and different pollution levels around the city of L′Aquila in central Italy. The results reveal a tight correlation between the particle composition, size, and the emission source. The analyses show also that the finer the particle, the higher its content of elemental carbon and organic compounds. Well-known carcinogens such as PAHs were detected among the identified organic compounds from both the rural and highly polluted sites.