Morphology box dimension and element contents of atmospheric particulate matters from motor vehicles in different regions were analyzed by using the field emissions scanning electron microscope(FESEM)

energy dispersive X-ray spectroscopy(EDX) and fractal theory. The results show that most of raw particulate matters from diesel engines are spherical and contain a great number of carbon and oxygen

and the particulate matters of small size are more agglomerative and therefore present greater box dimensions due to the large specific surface areas. The particulate matters of large size among those atmospheric ones collected from typical vehicle regions are prismatic and contain more calcium and silicon

which indicates there are many minerals and dust in big particulate matters. With the decrease in particulate matter size

the box dimension of each particulate matter from different sources increases.