He is a professor in gastrointestinal surgery at Peking University, the director of the Key Laboratory in "Malignancy Pathogenesis and Translational Research" under the Ministry of Education of the People's Republic of China, a fellow of the Chinese Academy of the Medical Sciences (CAMS), and a recipient of the Special Government Allowances of the State Council.

[12] In 1977, Ji took the first gaokao after the Cultural Revolution and was admitted to the Inner Mongolia Medical College; he graduated with a bachelor's degree in December 1982.

[4] In July 2011, Ji was appointed president of the Peking University Cancer Hospital / School of Oncology & Beijing Institute for Cancer Research, and in January 2013, director of the Key Laboratory in "Malignancy Pathogenesis and Translational Research" under the Ministry of Education of the People's Republic of China; his term as the president ended in June 2022.

[15] By 2019, the biobank had stored more than two million samples and contributed to 104 research projects, including the International Cancer Genome Consortium.

[20] The congress was a great success: there were 3,816 participants from 48 countries across the world, and 1,245 abstracts had been submitted including 99 oral presentations and 540 posters.

During his term (2017-2019), Ji advocated for his modularized gastrectomy on a global level and shared his experiences with surgeons from different countries; he also helped with the founding of the European Sub-Association of IGCA.

"[22] In 2019, Ji completed the world's first phase III randomized controlled trial on laparoscopic D2 gastrectomy and published his results on JAMA.