In China, species in the genus <em>Acorus</em> are used for many different purposes, viz., in traditional medicine, for rituals, and as ornamental plants. <em>Acorus calamus</em> (sweet flag) has been a symbolic plant in Chinese culture for many centuries and is used as a ceremonial object in festivals throughout the country. For other <em>Acorus</em> species in China, ethnobotanical records are few. During field investigations from 2006 to 2017, we interviewed 573 individuals representing ethnic groups such as the Miao, Yao, Buyi, Shui, Tujia, Dong, She, Maonan, Zhuang, Yi, and Han people. Various ethnobotanical approaches were adopted in the field surveys, including key informant interviews, semistructured interviews, participatory observation, direct observation, etc. The results have revealed a rich treasure trove of traditional knowledge on <em>Acorus</em> in China. Two species (<em>A. macrospadiceus</em> and <em>A. gramineus</em>) were used by ethnic groups as spices to add flavor to meat. Through the study found that all the species of <em>Acorus</em> had medicinal value, especially <em>A. tatarinowii</em>, deafness, blindness, and digestive disorders were among the conditions commonly treated using these plants. Traditional knowledge of the cultural, ethnomedicinal, and food values of <em>Acorus</em>, based on our recent literature surveys and field investigations in China is presented here. A better understanding of <em>Acorus</em> is vital for conserving the plants and the traditional knowledge associated with them.