In 2011, she won the women's chess tournament at the 2011 Summer Universiade in Shenzhen,[6] contributing to China's team gold medal.
[8] In 2013, she won the 3rd China Women Masters Tournament in Wuxi with a score of 6.5/9 points, 1.5 ahead of runners-up Valentina Gunina and Huang Qian.
[11] The following month, Tan won the 5th China Women Masters Tournament with 7/9, a full point ahead of second-placed Lei Tingjie.
[13] On December 1, 2015, Tan Zhongyi won the 1st China Chess Queen Match, a knockout tournament held in Taizhou, Zhejiang,[14] after defeating Ju Wenjun in the final in an armageddon game.
[18] In 2021, Tan achieved third place in the Women's Chess World Cup after winning against Anna Muzychuk with a score of 2.5 - 1.5.
[19] In 2022, Tan won the Women's World Rapid Championship in Almaty, Kazakhstan, after defeating local player Dinara Saduakassova in the tiebreaker.