This paper is aimed to present a corpus callosum and cerebellar anomaly with pathological findings in a 40-day-old, male, Golden Retriever puppy. It was stated that the dog rapidly deteriorated and died. On necropsy, after opening the skull, it was observed that the brain and cerebellum hemispheres were separated. In the detailed macroscopic examination, it was observed that the corpus callosum, interthalamic connections, which connect the brain hemispheres, were completely separated from each other. It was observed that the corpus callosum was more prominent in the right hemisphere but the anatomical structures of the left hemisphere were not evident. It was also observed that the hemispheres of the cerebellum were almost completely separated from the vermis region. It has been observed that brain connections can be achieved only by attachment between the midbrain and pons and continuing with the pons. Microscopic examination revealed no inflammatory reactions in the brain and cerebellum. Corpus callosum and cerebellar vermis anomalies in dogs have been reported before. However, split brain syndrome characterized by the loss of almost all connections of the brain and cerebellum in such severity that was observed in this case has not been previously reported.