AIM: To examine the evidence on culturally competent interventions tailored to the needs of people with diabetes from ethnic minority groups. METHODS: MEDLINE (NHS Evidence), CINAHL and reference lists of retrieved papers were searched from inception to September 2011; two National Health Service specialist libraries were also searched. Google, Cochrane and DARE databases were interrogated and experts consulted. Studies were included if they reported primary research on the impact of culturally competent interventions on outcome measures of any ethnic minority group with diabetes. Paper selection and appraisal were conducted independently by two reviewers. The heterogeneity of the studies required narrative analysis. A novel culturally competent assessment tool was used to systematically assess the cultural competency of each intervention. RESULTS: Three hundred and twenty papers were retrieved and 11 included. Study designs varied with a diverse range of service providers. Of the interventions, 64% were found to be highly culturally competent (scoring 90-100%) and 36% moderately culturally competent (70-89%). Data were collected from 2616 participants on 22 patient-reported outcome measures. A consistent finding from 10 of the studies was that any structured intervention, tailored to ethnic minority groups by integrating elements of culture, language, religion and health literacy skills, produced a positive impact on a range of patient-important outcomes. CONCLUSIONS: Benefits in using culturally competent interventions with ethnic minority groups with diabetes were identified. The majority of interventions described as culturally competent were confirmed as so, when assessed using the culturally competent assessment tool. Further good quality research is required to determine effectiveness and cost-effectiveness of culturally competent interventions to influence diabetes service commissioners.