Nan Xiaoheng started his professional football career when he was promoted to China League One side Shenyang Zhongze's first team squad.
[1] On 14 April 2014, he made his senior debut in a 6–0 away win over amateur team Shenyang Riverside in the 2014 Chinese FA Cup.
[3] On 12 March 2016, Nan made his debut for the club in a 2–1 away defeat against Shenzhen in the opening match of the season, coming on as a substitute for Tong Xiaoxing in the 69th minute.
[6] He failed to register for official league match due to transfer slot limit and played for reserve team instead.
He made his Super League debut on 11 March 2018 in a 2–1 home defeat against Beijing Sinobo Guoan, coming on for Xie Pengfei in the 79th minute.