Abstract: In this study,antibacterial activities of 6 spice samples were extracted by water or ethanol,then 2 spices whose antibacterial activities were more efficient were selected to analyze the inhibition effects on biofilm of Vibrio parahaemolyticus( VP).The results showed that,the garlic,cinnamon and clove had the stronger antibacterial activities,but the antibacterial activities of Chinese prickly ash,fennel and rosemary were lower.MIC values of the garlic,cinnamon were 6.25 mg / m L for VP,respectively.Sub- MICs of all the extracts could not only inhibit the biofilm formation,but also reduce the metabolic activity and the secretion of extracellular polysaccharide of cells in the biofilms. With the aid of confocal laser scanning microscope( CLSM),the increase of dead cell numbers and the decrease of biofilm polysaccharides could be observed obviously.