The N-coumarin-3-formacyl-N -substitute thiorea derivatives 4a～4f were synthesized by the reactions of different arylamine with coumarin-3-carbonyl isothiocynates which were prepared from coumarin-3-formacyl chloride and potassium thiocyanate. The structures of compounds 4a～4f were characterized by IR, ¹H NMR, MS techniques and elementary analysis, and biological activities were also originally studied. The results of biological activities showed that some compounds 4a～4f have potent antibacterial activities and quite evident auxin activities.

Key words: coumarin, thiourea derivative, synthesis, biological activity, antibacterial activity, auxin activity