More than three years. According to the query of official website of Anpeihua College, the graduation thesis file of Xi 'an Peihua College can be kept for more than three years, and it must be filed by the education department of the school, so it must be audited by the Education Bureau/KLOC-0 for more than 30 years before it can form its own judgment on graduates, so it should be kept for more than three years. Xi Anpeihua College (English name: Xi Anpeihua University), referred to as "Peihua", is located in Xi, Shaanxi Province, and is headed by the Education Department. It is the top 50 national innovation and entrepreneurship universities of the Ministry of Education, the pilot university of innovation and entrepreneurship education reform in Shaanxi Province, and the innovation and entrepreneurship base of colleges and universities in Shaanxi Province.