Trichinosis caused by Trichinella spiralis is a parasitic zoonosis with world-wide distribution, which impacts on the development of animal husbandry and food safety, and thus threatens human health. T. spiralis has the ability to evade the host immune response, which results in forming a long-term infection in the host. The previous studies indicated that a changed host immune state due to T. spiralis was an important reason for the evasion. Among the factors, cytokines, dendritic cells and regulatory T cells played an important role in the regulation of the host immune process.