Choline acetyltransferase (EC 2.3.1.6; abbreviated "ChAT") is an enzyme that is synthesized within the body of a neuron. It is then transferred to the nerve terminal via axoplasmic flow. The role of choline acetyltransferase is to join Acetyl-CoA to choline, resulting in the formation of the neurotransmitter acetylcholine.

Cholinergic systems are implicated in numerous neurologic functions. Alteration in some cholinergic neurons may account for the disturbances of Alzheimer disease. The protein encoded by this gene synthesizes the neurotransmitter acetylcholine. Alternative splice variants have been found that contain alternative 5' untranslated exons. Three of the four described splice variants encode identical 69 kDa proteins while one variant encodes both the 69 kDa and a larger 82 kDa protein.