Introduction: Global prevalence of diabetes and depression is increasing remarkably. Depression is 2–3 times more in diabetic population than non-diabetic people. Appropriate management mainly – diet, physical activity, medication, and regular screening and treatment can control, prevent, and delay diabetic complications. Aim: This study aims to assess the prevalence and impact of depression in diabetes self-management. Materials and Methods: This cross-sectional descriptive survey included 50 diabetic patients in the endocrinology outpatient department at selected medical college and hospital, Kolkata, from February 2021 to March2021. Depression and diabetic self-management were assessed through Patient Health Questionnaire-9 (PHQ-9) and Diabetes Self-Management Questionnaire (DSMQ), respectively. Based on the WHO’s five dimension of adherence, patients’ background information were collected. Results: PHQ-9 score indicates that 62% of the diabetics patients were having varied degree of depression mild (34%), minor (18%), and major depression (10%). DSMQ score indicates mean adherence in glucose management – 7.186, dietary control – 4.992, physical activity – 4.814, health-care use – 7.106, and sum scale – 6.12. About 60% of diabetic patients were having suboptimal adherence in diabetes self-management. There is a significant negative correlation (r = –0.382) between depression (PHQ-9) score and DSMQ score (P = 0.006). Conclusion: Depression is highly prevalent in diabetic population. Negative correlation between depression and diabetes self-management adherence indicates more the depression less the diabetes self-management.