A five-year-old male rabbit was presented with the request of necropsy. Post mortem examination revealed a mass in the cranial mediastinum. Histopathologically, it was seen that the mass consisted of a limited mesenchymal tissue with medium-sized mature lymphocytes and a large proportion (approximately 90%) of lymphoblast-like round cell infiltration. While tumour cells were stained positively for CD3, they were negative for CD79a. Pan-Cytokeratin was localized in small number of epithelial cells in the background. Histopathological and immunohistochemical evaluation showed that the case was compatible with thymic lymphoma and it was the first case reported in rabbits in Turkey.