Acute miliary pulmonary tuberculosis (AMPT), also known as acute disseminated pulmonary tuberculosis, is usually seen in infants and adolescents who are malnourished and immunocompromised. The first symptoms are mainly systemic toxic symptoms (such as high fever, chills, night sweats, etc.), while the respiratory symptoms (such as cough, sputum, etc.) are relatively mild. AMPT imaging has a special pattern of presentation and evolution. Early chest radiographs may be normal or consist only of increased lung texture, because at this time the corn foci are small and cannot yet be shown on the chest radiograph, or the diagnosis may be compromised by the poor quality of the film; a few patients may die before changes appear on the chest radiograph. About two weeks into the course of the disease, corn-like high-density shadows of “triple uniformity” in size, density and distribution, with a diameter of about 1 to 2 mm, begin to appear on chest films and chest CT. The performance of chest CT is earlier than that of chest X-ray, and the accuracy of diagnosis is also higher. Therefore, a “normal” early chest radiograph cannot negate the possibility of AMPT (as in this case). To reduce misdiagnosis and missed diagnosis. Sometimes, it is difficult to distinguish the small foci in the early stages of AMPT on a plain chest CT scan, and they appear as diffuse blurred shadows, which some call ground-glass opacity (GGO), and are difficult to distinguish from viral pneumonia, Pneumocystis carinii pneumonia, and other interstitial pneumonia. In fact, GGO refers specifically to low-density solid lesions on high-resolution CT (HRCT) images that do not obscure lung texture such as bronchial vessels. In this case, we performed HRCT scan at the same time and could show “triple homogeneous” diffuse cornea shadow, about 1 mm in diameter, in the center of lobules, interlobular septum and subpleural area, with random distribution, and the diagnosis of AMPT was made in combination with the clinical condition; anti-tuberculosis treatment was effective and confirmed the diagnosis. The diagnosis was confirmed by effective anti-tuberculosis treatment. Of course, the final diagnosis of AMPT requires pathogenic and histopathological evidence. In summary, the significance of chest CT is to detect lung lesions early when there is a high clinical suspicion of AMPT and the chest radiograph is negative. And HRCT has increased contrast than conventional CT and can show the structure of subtle lesions in the lung, thus distinguishing AMPT from other diffuse lesions in the lung. Therefore, HRCT of the chest is an important method for early diagnosis of AMPT.