Abstract: Objective: To summarize the HRCT manifestations of pulmonary lymphangitic carcinomatosis(PLC). Materials and Methods: The HRCT manifestations of 29 cases of PLC confirmed by pathology from October 2013 to June 2018 were analyzed retrospectively. All 29 cases underwent plain and enhanced HRCT scanning. Results: Among 29 patients with PLC, 17 patients were male and 12 patients were female, Age 30 to 79, the average age was 58 years old. Unilateral lung involvement was found in 16 cases(55%), and the incidence rate in the right lung was larger than that in the left lung. Bilateral lung involvement was found in 13 cases(45%) in two lungs. Localized distribution was found in 22 cases(76%), and diffuse asymmetrical distribution was found in 7 cases(24%). In 29 cases, irregular increase, thickening, disorder and unclear margin of lung texture(thickening of axial interstitium) were found, including 21 cases with multiple tiny nodule shadows in abnormal lung texture; 25 cases with irregular thickening of interlobular septum were found, 10 cases with small nodule like thickening(thickening of peripheral interstitium) were found; 5 cases with streaky shadow under pleura(thickening of peripheral interstitium) were found; There were 18 cases of irregular pleural thickening with multiple micro nodules, 14 cases of hilar and/or mediastinal lymphadenopathy, 10 cases of pleural effusion(more on the right side than on the left side), and 4 cases of pericardial effusion. Conclusion: In HRCT, PLC often shows the local or diffuse asymmetric thickening of pulmonary interstitium with multiple micro interstitial nodules, mild thickening of pleura with multiple micro nodules, ground glass shadow and small nodule shadow in the lung, hilar and/or mediastinal lymph nodes enlargement. HRCT has a high diagnostic value.