Abstract: Objective:To examine the features of multislice spiral computed tomography (MSCT) in micropapillary-predominant lung adenocarcinomas to improve the understanding of this type of lung cancer. Methods:The MSCT features of18cases with micro -papillary-predominant lung adenocarcinoma (micropapillary component >50%) confirmed by histopathology were analyzed retrospec-tively. Results:Among the 18cases of lung cancer, 1 was diffuse, 3 were central, and 14were peripheral lung cancer (PLC). The size of the adenocarcinomas in the 14PLC cases ranged from 1.3 cm to 8.5 cm, with an average of 3.56cm, including the size of 8 cases greater than or equal to 3 cm. Among the18cases, 13were lobulated,9 showed spicule signs, 7 showed pleural indentation signs, 5 had pleural adhesions,1 had bronchial truncation (i.e., cut-off sign), and4 were surrounded by obstructive inflammation. In addition, calcifi-cation was observed in one case, uneven density in two large lesions, air bronchus sign in four, and solid and ground-glass mixed densi -ty in two. Among the total number of cases, a variety of the measurable enhanced CT values ( Δ CT) of lesions were found in 16, ranging from 13HU to 80HU, with an average of47.5 HU, of which 15were cases ofΔ CT≥ 15HU and15were cases ofΔ CT≥ 20HU. Pleu -ral thickening was observed in two cases with pleural effusion, and pleural metastasis in one case was confirmed by histopathology. One case with pleural effusion suffering pleural metastasis was confirmed. Ground-glass density nodules in both lungs were observed in one case, with a few bilateral pleural and pericardial effusions. Eight cases had mediastinal or hilar enlarged lymph nodes with uneven density enhancement, and lymph node metastasis was pathologically confirmed in six cases. Lymph node metastasis was found in four cases, but no apparent enlargement of lymph nodes in MSCT was observed. Conclusion:Micropapillary-predominant lung adenocarci-nomas were common in non-smoking elderly female patients, whose lung cancer cases were mostly PLC. The typical features of PLC include lobulation, spicule, and pleural indentation signs. Solid density ranked first in the PLC cases, with evident enhancement and high rate of lymph node metastasis.