The invention provides a novel acetylcholine esterase inhibitor as well as a preparation method and application of the inhibitor, and particularly discloses an acridine substituted compound shown as aformula A and having bis-AChE binding site, and a preparation method and application of the compound as an acetylcholine esterase inhibitor. The prepared novel compound shows the effect of well inhibiting acetylcholine esterase, and has application values in preparation of a drug for treating and preventing Alzheimer's Disease (AD).