On March 6, 2019, Ning announced his retirement from competitive swimming through his Weibo account, on his 26th birthday.

[9] His parents took him to a swimming school to help him overcome his fear of water and to improve his physical health.

Local coach Guo Hongyan noticed Ning's quick grasp on learning different strokes and techniques.

Because he suffered from chronic bone calcification on his right knee, he switched from individual medley to sprint freestyle.

[20] At the Chinese National Swimming Championships, Huangshan, Anhui, China on October 26, Ning won a gold medal in 50-meter butterfly with a time of 24.13.

[22] He was not in his best physical state at the games due to a wrist injury sustained a few months prior to the competition.

On September 24, in the men's 4 × 100-meter free relay, teamed with Yu Hexin, Lin Yongqing, Sun Yang, Ning swam the fourth leg and ensured China finished in first place and set a new Asian record with a time of 3:13.47.

On September 26, in the men's 4 × 100-meter medley relay, with Xu Jiayu, Li Xiang, Li Zhuhao, swimming the fourth leg, Ning overtook strong rival, Japan's Shioura Shinri in the last 50 meters and helped China win gold in a time of 3:31:37.

[24] Continuing his dominance in the freestyle sprints at the Chinese National Swimming Championships, Huangshan, Anhui, China, Ning broke his previous Incheon Asian record of 47.70 in the 100-meter free with a new time of 47.65 on October 17.

[27] At the 2014 FINA Swimming World Cup in Beijing, Yu Hexin, Suo Ran, Lu Ying, with Ning swam the fourth leg in the mixed 4 × 50-meter medley relay, finished in first place with a time of 1:40.10.

In the men's 4 × 100-meter free relay heats, he swam the second leg with a time of 46.13, putting China in 10th place overall.

In an interview with CCTV5 Sports, Ning confirmed that he had not fully recovered from his wrist injury and was hoping to undergo more effective treatment in preparation for the upcoming World Championships.

[32] Competing for the Chinese National swimming team at the 16th FINA World Aquatics Championships in Kazan, Russia, Ning with teammates Yu Hexin, Lin Yongqing and Jiang Qiheng competed in the 4 × 100-meter freestyle relay on August 2.

[35] In the interview after the race, Ning credited his success to the six weeks he spent training under Australian Coach Matthew Brown.

On August 7, Ning raced in the men's 50-meter freestyle, finishing in 14th place with a time of 22.43 and advancing to the semifinal.

[40] Ning received the CCTV Sports Award for Best Male Athlete in 2014 for his achievements in sprint freestyle.

Ning often appears in advertisements or promotional events alongside other members of the Chinese National Swimming Team.

Ning, as a very popular swimming icon nationwide, has had various appearances in magazine covers, commercial posters and TV shows.

Ning was forced to stop his training from Australia, returned to China, found his meal card locked, and was threatened to leave his apartment, which was provided by the National Swimming Center.

Since then, the General Administration of Sports strongly criticized Ning's extensive off-the-court activities.