Not illegal. According to China's medical policy, Chinese medicine decoction substitution is a kind of Chinese medicine service until April 2023 1 1. It has been recognized and supervised by the state and supported by medical insurance to a certain extent. Chinese medicine is prepared in legal medical institutions and provided by Chinese medicine practitioners with corresponding qualifications and practice certificates, which is in line with the law. In order to obtain better service and guarantee, it is suggested to choose a legal medical institution, consult a qualified and practicing doctor of traditional Chinese medicine, and use traditional Chinese medicine instead of decoction.