Abstract Aims Common Psychiatric Disorders (CPDs) are associated with the development of overweight and obesity, the strongest risk factors for the onset and maintenance of Type 2 Diabetes mellitus (T2D). To the best of our knowledge, this is the first study to assess the prevalence of CPDs in patients with T2D in Italy. Methods This is a monocentric cross-sectional study; n = 184 T2D patients were screened for CPDs using the Patient Health Questionnaire (PHQ). Primary outcome was to evaluate the prevalence of CPDs. To assess association between CPDs and risk factors, we have utilized univariable logistic regression models. Results 64.1% were men, median age was 67 (59–64) and median BMI 27 (25–30) kg/m². The 42.9% tested positive for one or more mental disorders, 25.6% for depression. Patients with higher BMI (p = 0.04) had an increased likelihood of testing positive to the PHQ. Patients who had implemented lifestyle changes (p < 0.01) and were aware that mental health is linked to body health (p = 0.07) had a reduction in the likelihood of testing positive. Conclusions Prevalence of CPDs in T2D patients is higher than in the general population. Since CPDs favor the onset and subsistence of T2D, integrated diabetic-psychiatric therapy is required for improvement or remission of T2D in patients with comorbid CPDs.