[3][1] Zhao graduated from Changsha Railway College (merged to form Central South University) with a major in foreign language studies.

[4] When he served as a first secretary at the Embassy of China in the United States, he enrolled at the Korea Development Institute from February to December 2005 and received a master's degree in public policy.

[19][20] Although it had been banned in China in 2009, Zhao joined Twitter in 2010, becoming one of the first envoys of the Chinese government to use the social media platform.

[28][16] On 5 March 2020, Zhao gave a press conference in Beijing and responded to an American TV host's demand that the Chinese should "formally apologize" for the novel coronavirus pandemic.

[31] On 12 March Zhao, without asking for permission from his superiors,[32] appeared to promote a conspiracy theory that the United States military could have brought the novel coronavirus to China,[33][34][31][35][36] tweeting first in English and separately in Chinese:When did patient zero begin in US?

[37][38]The allegation was apparently linked to the United States' participation at the 2019 Military World Games held in Wuhan in October,[35] two months before any reported outbreaks.

[38] Zhao accompanied his post with a video of Robert Redfield, director of the US Centers for Disease Control and Prevention, addressing a US Congressional committee on March 11.

"[31] The US State Department summoned Chinese ambassador Cui Tiankai on March 13 to protest about Zhao's comments.

[38][39] During an interview on Axios on HBO, Cui distanced himself from Zhao's comments and said speculating about the origin of the virus was "harmful".

[42] On August 11, 2021, Zhao Lijian posted a tweet supporting the Chinese conspiracy theory that SARS-CoV-2 virus was developed by the United States military at Fort Detrick.

[46] Associated Press claimed that authorities in China were using forced birth control amongst Uyghur people, whilst encouraging larger families of Han Chinese.

"[50][51] On 19 November 2020, the Five Eyes intelligence-sharing group said China's imposition of new rules to disqualify elected legislators in Hong Kong appeared to be part of a campaign to silence critics and called on Beijing to reverse course.

[53] On 30 November 2020, Zhao posted on his personal Twitter account "Shocked by murder of Afghan civilians & prisoners by Australian soldiers.

China rejected the demands for an apology on the following day,[60] while Twitter also refused Morrison's request to remove Zhao Lijian's tweet.

[65] The incident had the effect of unifying Australian politicians in condemning China across party lines, while also drawing attention to the Brereton Report.

A spokesperson for the US State Department likewise accused the Chinese foreign ministry of hypocrisy for using Twitter at all when it is blocked in China.

[71] The Taiwanese government expressed concern about the Chinese foreign ministry's use of a manipulated image in an official tweet.

[77][78] Britain's Defense Ministry said: "These narratives are long standing but are currently likely being amplified as part of a retrospective justification for Russia's invasion of Ukraine".

[81] When asked about what that meant, Zhao said that "If the U.S. side is bent on going its own way, China will take strong measures to resolutely respond and counteract" and that "The United States should be held responsible for any serious consequences.