Neuroprotective effect of deprenyl on motoneurons of spinal cord after axotomy of peripheral nerves such as sciatic has been well established. Deprenyl is an inhibitor of monoamine oxidase type-B (MAO-B). The main function of this agent is the release of neurotransmitters from pre-synaptic terminals. Acetylcholine is a neurotransmitter that is synthesized by choline acetyltransferase (ChAT) and is widely used as a marker to assess the function of neurons. Synaptophysin is one of the synaptic vesicle neuronal terminal residual proteins which is also used as a marker for some neurotransmitters.The aim of this research was to study the effect of deprenyl (2.5 mg/kg) injection on synaptophysin and ChAT immunoreactivity. The intraperitoneal injection of deprenyl was done following axotomy and continued for 21 days. Then, the animals were perfused with paraformaldehyde (4%) and spinal cord segment L4-L6 proccessed for immunohistochemistry. The results obtained in this study showed that deprenyl-treated axotomized mice had higher ChAT and synaptophysin expression as compared to untreated axotomized animals.