Chang Chong-Jen (18 September 1907 - 8 October 1998), (also Zhang Chongren, 张充仁 & 張充仁), was a Chinese artist and sculptor best remembered in Europe as the friend of Hergé, the Belgian comics writer and artist and creator of The Adventures of Tintin. The two met when Chang was still an art student in the Brussels art school, Academie Royale des Beaux-Arts.
When Hergé decided to create a story that would put Tintin in China, he was advised to do more research by other, to avoid controversy. The subject of China was a very delicate matter in those times, and Hergé agreed. Sent to Hergé to help him learn more about China, Chang first met Hergé in 1934. The two men, both 27 years old, soon became fast friends, and both learned much from each other.
The character Chang from The Blue Lotus and Tintin in Tibet, was based on Chang Chong-Jen, as it was he who taught Hergé about China and inspired him to adopt a more realistic style of writing and drawing. Chang also helped Hergé with the Chinese text used for The Blue Lotus. Hergé decided to add the character Chang out of gratefulness after the real Chang Chong-Jen had left.
Chang returned to Europe for a reunion with Hergé in 1981, after receiving an invitation from the French government. Apparently, when the two men saw each other, they "rushed to each other with open arms", as stated in Pierre Assouline's biography of Hergé.