He joined the Ministry of Foreign Affairs in 1972, after previously served as a worker at the Shanghai City Pujiang Electric Meter Factory from 1968 to 1972.

[2] Yang studied international relations at Ealing College, University of Bath, and London School of Economics from 1973 to 1975.

Affected by the Cultural Revolution, he dropped out of school in 1968 and entered Shanghai Pujiang Electric Meter Factory as a worker.

From 2001 to 2006, He received a Ph.D. in world history from Nanjing University through distance education while serving as Chinese Ambassador to the United States from 2000 to 2004 and later Deputy Minister of Foreign Affairs.

[5] During the late 1970s, Yang served as an interpreter for George H. W. Bush, who worked at the US Liaison Office in China at the time, and his family during a visit to Tibet.

During the Tiananmen Square Protests of 1989, Yang accompanied Wan Li, the chairman of the National People's Congress, on a trip to North America.

[8] During his tenure as ambassador to the United States, Yang worked to ease the tensions between the two countries following the 2001 mid-air collision between a U.S. EP-3 spy plane and a Chinese fighter jet off the coast of Hainan Island in the South China Sea.

In 2004, Yang had a heart attack that was nearly fatal; he was taken to the George Washington University Hospital and treated by doctors of Vice President Dick Cheney.

[3] At the first plenary session of the 12th National People's Congress in March 2013, Yang Jiechi was elected as State Councilor.

After the Leading Group was upgraded to the Central Foreign Affairs Commission in March 2018, Yang served as its director until 1 January 2023.

In 2017, Yang incorporated the term "Great changes unseen in a century" into the CCP's rhetoric, describing it as a guiding tenet of Xi Jinping Thought on Diplomacy.

On 1 January 2023, Yang Jiechi officially retired from politics after he stepped down as the director of the Office of the Central Foreign Affairs Commission.

According to Sinologist Peter Martin, Yang's daily routines as a diplomat included reading The New York Times every day and talking about details from its content during conversations with his counterparts.

[6] During interactions before the start of official meetings with foreign counterparts, Yang has been described as relaxed, telling jokes and anecdotes.