Before entering the entertainment industry, Li Dongheng studied at the undergraduate school of the School of Foreign Languages of the University of Electronic Science and Technology of China, majoring in English and French, and minoring in Business Management.
In 2007, he participated in the Chongqing Satellite TV's "First Love" comprehensive actor talent show and made his debut. The title of national champion allowed Li Dongheng to start his acting career.
In 2008, he acted in the ancient costume detective drama "Ten Great Mysteries" and played the role of Prince Alahan. In the same year, he participated in the TV series "Basket of Flowers".
In 2011, he signed with Beida Xingguang Group. That same year, he starred in the TV series "Iron-Blooded Man Xia Minghan" directed by Shen Haofang, portraying Zhu Tingli, a character with a special revolutionary background.
In 2012, he starred in the independent film "Willow", which was shortlisted for the 2014 London Film Festival competition. That same year, he appeared in a series of microfilms produced by CCTV Movie Channel called "Love @ Tongxiang", playing the role of bar owner Lv Song.
In 2014, he co-starred with Li Xuejian in the movie "River Far Away," portraying the young and old heroic character Chen Nuo. That same year, he appeared in the urban romantic comedy "Dating Expert" starring Zhu Yuchen and Guo Jingfei, playing the role of young white-collar worker Wang Xuzhu.
In January 2015, he appeared in the historical palace drama "The Legend of Wu Meiniang" starring Fan Bingbing and Zhang Fengyi, playing the role of the Tang Dynasty general Xue Wancha. In February, he co-starred with Raymond Lam and Kenneth Tsang in the ancient martial arts drama "The Six Doors", portraying the martial artist Xiao Jun outside the Pass.
In July 2015, he portrayed Li Lei in the modern romance drama "Dear Translator".
In 2016, this drama gained popularity on Hunan Satellite TV. That same year, he collaborated with Yang Mi and Mark Chao in the ancient costume drama "Eternal Love", portraying Lian Song. The drama was directed by Lin Yufen and styled by the renowned designer Zhang Shuping.
In 2016, the investigative drama "Mystery Sand" starring Li Dongheng premiered in the prime time on Dragon TV and achieved the highest ratings.