With the development and application of biological agents, the treatment effect was considerable degree improvement on refractory corn's disease. However, there are quite a part of the CD patients lost response during treatment of using response. Moreover, due to various reasons, there still a lot limited on the using of biological agents in China, that make quite a part of the refractory CD patients lack of further medical treatment options. There has been a RCT study which prove that thalidomide effect and safety on treating refractory CD or who were lost response by using biological agents in Italy, but the object of study is only limited in children and adolescents. There are some small sample studies also confirmed the efficacy and safety on refractory corn's disease by using thalidomide, but need more RCT evidence.