The Yongle Emperor, written in traditional Chinese, is read as 永樂帝.

In simplified Chinese reads as: 永乐帝 and in pinyin: Yǒnglèdì.

Wade-Giles: Yung-lo Emperor; IPA: [jʊ̀ŋlɤ̂]) (2 May 1360 – 12 August 1424), born Zhu Di (朱棣), was the third emperor of the Ming Dynasty of China, reigning from 1402 to 1424. His Chinese era name Yongle means "Perpetual Happiness".

He was the Prince of Yan (燕王), possessing a heavy military base in Beijing. He became known as Chengzu of Ming Dynasty (明成祖 also written Cheng Zu, or Ch'eng Tsu (Cheng Tsu) in Wade-Giles) after becoming emperor (self title). He became emperor by conspiring to usurp the throne which was against the Hongwu Emperor's wishes.

He moved the capital from Nanjing to Beijing where it was located in the following generations, and constructed the Forbidden City there between 1406 and 1420. After its dilapidation and disuse during the Yuan Dynasty and Hongwu's reign, the Yongle Emperor had the Grand Canal of China repaired and reopened in order to supply the new capital of Beijing in the north with a steady flow of goods and southern food supplies. He commissioned most of the exploratory sea voyages of Zheng He. During his reign the monumental Yongle Encyclopedia was completed. Although his father Zhu Yuanzhang was reluctant to do so when he was emperor, Yongle upheld the civil service examinations for drafting educated government officials instead of using simple recommendation and appointment.

The Yongle Emperor is buried in the Changling (長陵, "Long Mausoleum") tomb, the central and largest mausoleum of the Ming Dynasty Tombs.