Purpose Cancer is of increasing prevalence in less-developed countries. However, research on the patients' quality of life (QoL) in these countries is very limited. The aim of this study was to examine QoL of cancer patients in Africa. Method A sample of 256 cancer patients treated in an Ethiopian hospital was examined with the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire EORTC QLQ-C30, the Multidimensional Fatigue Inventory, and the Hospital Anxiety and Depression Scale. A group of 1664 German cancer patients served as a comparison group. Results Most of the scales of the EORTC QLQ-C30 showed acceptable reliability in the Ethiopian sample. Compared with the German cancer patients, the Ethiopian patients showed lower QoL in most dimensions, especially in financial difficulties, physical functioning, pain, and appetite loss (effect sizes between 0.52 and 0.75). Illiteracy, tumor stage, and treatment (surgery and chemotherapy) were associated with QoL in the Ethiopian sample. QoL was strongly correlated with fatigue, anxiety, and depression. Conclusion The EORTC QLQ-C30 is a suitable instrument for measuring QoL in Ethiopia. The detriments in QoL in the Ethiopian patients indicate specific cancer care needs for the patients in a developing country.