Acetylcholinesterase enzyme is a serine hydrolase, most commonly located at the site of neuromuscular attachment and cholinergic brain synapses, which terminates synaptic transmission through hydrolysis of acetylcholine neurotransmitter. In cholinergic hypothesis which is one of the proposed hypotheses about the cause of Alzheimer s disease, the Alzheimer-related dementia is attributed to the reduced level of acetylcholine neurotransmitter in the cortex and other regions of the brain. Therefore, the administration of acetylcholinesterase inhibitors serves as one of the powerful Alzheimer therapeutic strategies. In this enzyme, the residues involved in substrate binding and catalytic activity are located at the depth of a narrow hydroponic gorge located on the surface of the enzyme. The entrance of this gorge is called the peripheral anionic site. In the present work, the interaction of a synthetic novel acridine derivative with the acetylcholinesterase enzyme has been investigated using molecular docking method. It should be noted that based on the previous experimental work, the high ability of this compound to inhibit acetylcholinesterase enzyme had been proven. In order to conduct this research, PDB file of the enzyme was downloaded from PDB site and PDB file of the inhibitor was prepared using ChemDraw software. Then the required molecular docking inputs were provided by AutoDockTools software. Finally, the molecular docking was performed using AutoDock Vina software and the results were analyzed using PyMol, Chimera, and LigPlot software. The results of this study indicate that this compound is longitudinally introduced into the hydrophobic catalytic gorge, but does not penetrate to the depth of the gorge. In fact, this inhibitor interacts with the residues of the peripheral anionic site and thus blocks the entrance of substrate to the active site. The results obtained from this study could be used to design new effective drugs for the treatment of Alzheimer s disease.