〔Abstract〕 To investigate the CT features of lung adenocarcinoma with ground glass nodules(GGN) on thin slice CT(TSCT) and to compare with the pathological classification. A total of 83 pulmonary ground glass nodules were collected retrospectively. According to the pathological results, the lesions were divided into pre-invasive lesions group with 20 lesions, microinvasive adenocarcinoma(MIA) group with 32 lesions, and invasive adenocarcinoma(IAC) group with 31 lesions. The appearance of nodules with different pathological types on thin-slice CT was analyzed. Among 83 lesions, 34 1 esions were pure ground glass opacity(pGGN),while 49 lesions were mixed ground glass opacity(mGGN).pGGN was observed in pre-invasive lesions group(18/20,90.0%), MIA group(16/32,50.0%) and IAC group(0/31,0%), respectively. Among the 3 groups, the proportion of foliation sign, air bronchi sign, vascular cluster sign and pleural depression sign showed an increasing trend, while the proportion of round/quasi-round sign and clear sign of tumor lung interface showed a decreasing trend. There were statistically significant differences in round or quasi-round, lobulated sign, clear lung interface of tumor, air bronchi sign, vascular cluster sign and pleural depression sign(P<0.05). There were statistically significant differences between pre-invasive lesions group and IAC group in round or round shape, lobulation sign, clear lung interface of tumor, air bronchi sign, vascular cluster sign and pleural depression sign(P<0.05). There were statistically significant differences between MIA group and IAC group in terms of roundness, lobulation sign, clear lung interface of tumor and vascular cluster sign(P<0.05). The manifestations of GGN of different pathological types on TSCT have certain specificity, and familiarity with the manifestations of TSCT is conducive to the diagnosis and differential diagnosis of pre-invasive lesions, micro-invasive adenocarcinoma and invasive adenocarcinoma.