Five years. Official website of China Industrial and Commercial Bureau showed that the longest use time of food business license in China is five years, and it needs to be re-examined after five years, that is, the validity period of food business license is five years. A food business license refers to a food business license issued by a legal entity engaged in food sales and catering services in People's Republic of China (PRC) with the approval of the food and drug supervision and administration department.