Aims To develop a psychometric measure of diabetes acceptance. Methods An item pool was developed and pilot-tested using a sample of 220 people with diabetes; item selection resulted in the 20-item ‘Diabetes Acceptance Scale (DAS)'. 606 people with diabetes were then cross-sectionally assessed with the DAS to evaluate its reliability, validity and clinical utility; concurrent measurements included diabetes-related coping (FQCI), diabetes distress (PAID-5), depressive symptoms (PHQ-9), quality of life (EQ-5D), self-management (DSMQ), glycaemic control (HbA 1c ) and complications. Results Internal reliability was high (Cronbach's α = 0.96). Factorial and criterion-related results supported validity. Higher diabetes acceptance scores correlated with more functional coping styles, lower distress and depression levels, higher treatment adherence, better glycaemic control and better quality of life (all P 1c values over 9.0% (75 mmol/mol), two times more likely to be diagnosed with long-term complications and each over two times more likely to have had episodes of severe hypoglycaemia and ketoacidosis in the past year; the prevalence of major depression in this group was fivefold increased (all P Conclusions The DAS is a reliable and valid tool to measure diabetes acceptance. It may help identify patients with significant problems of accepting diabetes, a putative high-risk group in need of tailored care and support.