Abstract: Twenty-one novel 6,7-methylenedioxy-4-chromanone derivatives were synthesized from sesamol via the reaction of etherification,Friedel-Crafts acylation and adol condensation.Their structures were confirmed by 1H NMR,13C NMR,MS and IR.Preliminary antifungal activity test showed that all of the synthesized compounds have different inhibition on eight tested plant pathogenic fungi at the concentration of 50 mg/L.Specifically,the inhibition rates of chromanone against Botrytis cinerea and Alteraria alternata were up to 87.9% and 56.7%.d1 and d6 were 72.2% and 52.5% against Mangnaporthe grisea,while the inhibition rate of compound d6 to Curvulavia lunata and d9 to Valsa mali were above 70% under the concentration of 50 mg/L.