Aspiration is defined as accidental entrance of foreign matter into the lower respiratory tract, and is a common event and can occur in healthy individuals. The type of aspiration-induced lung diseases depends on the quantity and nature of the aspirated material, the chronicity, and the host responses. Aspiration into the airways and lungs can cause a wide spectrum of lung diseases with various manifestations in adults. Diseases with predominantly airway manifestation include foreign body aspiration and diffuse aspiration bronchiolitis. Diseases with predominantly lung parenchymal manifestation include acute diseases such as aspiration pneumonia, aspiration pneumonitis, and near drowning, and chronic diseases such as chronic exogenous lipoid pneumonia and chronic interstitial lung disease. Definitive diagnosis of aspiration-induced lung diseases is challenging to make. Awareness of radiologic findings associated with these diseases is essential for accurate diagnosis and management of these diverse aspiration-induced lung diseases.