The present invention provides a body fat-reducing agent containing a processed pueraria flower as an active component. The body fat-reducing agent has a superior body fat-reducing effect. Furthermore, the body fat-reducing agent may contain at least one of a lipid absorption suppressing component and a lipid metabolism promoting component. A food product, which contains the body fat-reducing agent, provided according to the present invention has superior effects of preventing body fat accumulation and reducing body fat.