BACKGROUND: The Mayo Elbow Performance Score (MEPS) is a rating system consisting of four dimensions to evaluate elbow performance. It is a common tool for assessment of elbow impairments worldwide. We determined the validity and reliability of its German version (MEPS-G) after cross-cultural adaptation. METHODS: Six investigators examined 57 patients with elbow pathologies. The MEPS-G was compared to validated elbow scores such as the German versions of DASH, the Oxford Elbow Score, pain level and subjective elbow performance on a VAS. Inter-rater reliability (IRR) and validity of the score and its dimensions were also reviewed. Verification was performed using the intraclass correlation coefficient (ICC), the prevalence and bias with adjusted Kappa (PABAK) and the Spearman correlation. RESULTS: The IRR of the MEPS-G score was moderate (ICC (2.1) = 0.65). The IRR of the four individual dimensions was moderate to high (K = 0.55 -0.81). Validity for the sum score (r = 0.52-0.65) and the dimensions pain (r = 0.53-0.62), range of motion (r = 0.7) and stability (r = - 0.61) was verified. The function subscale reached insufficient validity (r = 0.15-0.39). CONCLUSION: The MEPS-G is not sufficiently valid, which is consistent with its English version. The patient-based dimensions were a weakness, demonstrating high risk of bias. There is no general recommendation for the utilization of the MEPS-G as outcome measurement for patients with elbow pathologies.