PROBLEM TO BE SOLVED: To provide a plant-derived antibacterial agent that is safe for even infants, pets and the like.SOLUTION: The present invention provides an antibacterial agent production method for producing an antibacterial agent comprising a plant-derived component as an active ingredient, comprising a raw material blending step of blending vetiver and lemongrass for use as blending raw materials, a component extraction step of obtaining aqueous solution being a product from the component extraction of the blending raw materials, and an addition step of adding the aqueous solution as an active ingredient.SELECTED DRAWING: Figure 1