The invention relates to the field of medicinal chemistry and pharmacotherapeutics and provides a 2-substituted arylethenyl-N-methylated quinoline derivative, a synthesis method thereof and an application of the 2-substituted arylethenyl-N-methylated quinoline derivative to the preparation of a drug for treating Alzheimer disease. The 2-substituted arylethenyl-N-methylated quinoline derivative has the chemical formula shown in the specification, wherein R1 in the formula is hydrogen, methylpiperazine, piperidine, morpholine, ethoxylpiperazine, dimethylaminoethylpiperazine or dimethylaminopropylpiperazine; R2 is para-substituted chlorine, fluorine, hydroxyl, methoxyl, dimethylamino, diethylin, methylpiperazine and morpholine, or ortho-substituted hydroxyl and methoxyl or meta-substituted methoxyl and nitro; R4 is hydrogen, chlorine, fluorine, hydroxyl, methoxyl, dimethylamino, diethylin, methylpiperazine or morpholine; R2 and R6 are hydrogen, hydroxyl or methoxyl; R3 and R5 are hydrogen, methoxyl or nitro. Experiments prove that the 2-substituted arylethenyl-N-methylated quinoline derivative provided by the invention has anticholinesterase activity, anti-Abeta aggregation and antioxidant activity.