The incidence and prevalence of Crohn’s disease is on the rise worldwide today. Over the past few years, there is evidence that the incidence of Crohn’s disease has been increasing year by year worldwide. The incidence and prevalence of Crohn’s disease appear to be beginning to stabilize in areas of high prevalence in Western countries. In contrast, Crohn’s disease has been reported to be increasing year by year in low prevalence regions such as Asia, southern Europe and South America. The results of a large prospective population-based study on the prevalence of IBD conducted in the Asia-Pacific region showed that China has the highest prevalence of Crohn’s disease in Asia. There are two reasons for this: one is the growing awareness of the disease among clinicians and patients. Crohn’s disease was only known to Chinese physicians after about 1970, so there was no way to diagnose it. In the past, many physicians were unaware of the disease, so they were unable to diagnose it when faced with patients with Crohn’s disease. As people became more and more concerned about Crohn’s disease, so more and more Crohn’s disease patients were diagnosed. The second reason may be the Westernization of the Chinese diet, with a high protein, low fiber diet and increasing intake of dairy products, hence the increasing number of Crohn’s disease. Of course, this is only inference, because the causal relationship between dietary habits and Crohn’s disease is not clear at present. The peak incidence of Crohn’s disease patients occurs between the ages of 15 and 40 years. However, a bimodal age distribution of Crohn’s disease incidence has been observed in Western populations, i.e., a second peak in incidence may exist between the ages of 50 and 80 years. In contrast, in the Asian Crohn’s disease patient population, there is no bimodal age distribution in either the incidence of Crohn’s disease, i.e., the majority of Crohn’s disease patients in China are between 15 and 40 years of age. The reason for the prevalence in young people is not clear and may be due to the association of the disease with diet and genetic inheritance.