Objective Analysis of CT manifestations of Diabetes complicated with tuberculosis ,in order to improve the level of CT diagnosis. Methods 104 cases of diabetes complicated with tuberculosis were randomly selected as the study group,104 cases of patients with pulmonary tuberculosis alone as a control group。Comparison of two groups of patients with chest CT performance analysis. Results Lesions occur in the rare site of tuberculosis, The number of patients in the observation group is more than in the control group.There were significant differences between the two groups(P<0.05).In common site of tuberculosis, Comparison of the two groups is not a statistically significant difference(P>0.05). The distribution range of lesions of the observation group is wider than in the control group, Comparison of the results of the two groups were significantly different(P<0.05). Air bronchogram and multiple moth-eaten holes of the observation group is more than the control group. Conclusion Diabetes complicated with tuberculosis, Two lung lesions distribution range is wide, Rare part is also more common, The lesion is large, Patchy distribution of multi-leaf segments, May have air bronchograms and multiple moth-eaten holes large patchy.