BACKGROUND: Depression and cardiovascular diseases (CVD) are two common conditions that account for a high proportion of morbidity and mortality worldwide and in Germany. The objective of this study is to examine whether the risk of developing depression in persons with prevalent chronic CVD is elevated compared to persons without CVD and whether it varies by sex and age group. METHODS: This observational case-control study is based on German statutory health insurance claims data from 2015 to 2019 (N = 2,229,042). The study population comprises persons with a CVD diagnosis in 2016 and without depression or acute major CVD event in 2015-2016 (N = 173,774). A control group was built by 1:1 matching by sex, gender and age. Cox regression models estimated the risk of developing depression during the observation period (2017-2019) while adjusting for several comorbidities. Results are presented stratified by sex and age group. RESULTS: The presence of chronic CVD increased the risk of developing depression in men and women and in all examined age groups. This relationship between chronic CVD and depression appeared to be particularly pronounced in younger men aged under 55 years (HR = 1.33, 95 %-Confidence Interval (CI) = 1.14-1.54). However, risk of developing depression was much higher in women (with and without CVD) than in men (HR = 1.53, 95 %-CI = 1.46-1.61). CONCLUSIONS: This study underlines the importance of mental health services for patients with cardiovascular diseases. Given the impact of depression on re-hospitalization, self-care and all-mortality in patients with chronic cardiovascular disorders, a screening for depressive symptoms in this patient group is highly recommended.