Smile arc is one of the most important indicators in smile aesthetics. Stomatologists can adjust the smile arc through orthodontic treatment to improve the smile. This article will review the definition and research methods of smile arc, the influencing factors of smile arc on smile aesthetics and the corresponding orthodontic clinical treatment strategies, in order to provide a more scientific, more accurate and more efficient treatment plan for orthodontic clinical design, so as to achieve better clinical treatment goals.