Cholinesterase activity of the human nasal mucosa was demonstrated with a histochemical technique according to Karnovsky and Roots. Rich cholinergic innervation was observed around the arteries and arterioles and a few cholinesterase-positive fibers were detected around the veins. Both serous and mucous glands were encapsulated by many nerve fibers presenting intense cholinesterase activity. The duct of the gland and the epithelial layer failed to show cholinesterase activity. The author’s conclusion is that these positive nerve fibers were peripheral parasympathetic nerve fibers which possibly play a major role in stimulating the secretion of the nasal glands and the dilatation of the blood vessel