We report on a 69-year old male patient who presented with vague depressive symptoms and loss of weight accompanied by lack of appetite, ageusia and anosmia. The patient died of bronchial pneumonia, and neuropathological examination revealed a so-called limbic encephalitis. The paraneoplastic origin of this case was later confirmed by discovery of a clinically inapparent, indolently growing small cell lung cancer. This case illustrates the difficult clinical diagnosis of paraneoplastic limbic encephalitis and the need for a close cooperation of pathologists and neuropathologists in the clarification of such cases.