Nano-particulate matters (NPM) induced the lung injury in mice were evaluated using quantitative micro-computed tomography in the present article. It is an important negative effect of health problems that NPM exposure provokes changes in the lung injury. The micro-computed tomography (CT) to assess lung injury in mouse models has been investigated. The dynamic structural changes in a NPM-induced lung injury mouse mode were monitored. Adults female BALB/C mice were repeatedly exposed to NPM, and micro-CT scans were performed at day 0, 3, 5 and 9. Lung samples were also collected for histological analysis at each time point. The total lung volume, the injured lung volume, and the normal lung volume were defined and calculated volume during the phase of NPM-exposure on the mice. The total and injured lung volumes of NPM-exposed mice were significantly larger than those of the mice at day 5 and 9. The data from micro-CT was consistent with alveolar enlargement and destruction by histological quantification from pathological section. The study for NPM-induced lung injury model by micro-CT may extend our understanding of the distinct pathophysiology of NPM induced lung injury in mice.