Abstract: Solid horn is an important component in ultrasonic vibration system,often used in high power ultrasound applications.New advances in various design methods of ultrasonic solid horn is reviewed,for example,conventional analytical method,methods of equivalent circuit,mechanical impedance,transfer matrix,finite element,and apparent elastic modules,etc.Characteristics of different methods are compared,and problems that need further studies are pointed out such as seeking a unified expression for performance factors of solid horns with common shape functions.