Abstract: In order to find coumarin thiazole derivatives with high antifungal activity, thirteen coumarin thiazole derivatives 8a-8m which have not been reported in literature were synthesized by using 7-hydroxycoumarin as raw material and modifying hydroxyl group. The structures of the products were characterized by ~1H NMR and ¹³C NMR. The growth rate method was used to determine the antifungal activity of the compound against the pathogenic fungi of sesame: Macrophomina phaseolina, Fusarium oxysporum and Corynespora cassiicola. The results show that all the compounds have certain antifungal activity at the concentration of 500 μg/mL. Among them, the inhibitory activity of N-（4-（3, 4-dichlorophenyl） thiazol-2-yl）-2-（2-oxy-coumarin-7-methoxy） acetamide（8a） is better than dimethomorph against Macrophomina phaseolina, and is equivalent to dimethomorph against Fusarium oxysporum and Corynespora cassiicola. N-（4-（4-thiophen-2-l） thiazol-2-l）-2-（2-oxy-coumarin-7-methoxyxy） acetamide（8k） is close to the control drug in inhibiting the activity of the Macrophomina phaseolina.