Staff at the US' consulate in Chengdu prepared to leave yesterday, removing the insignia from the building as well as what appeared to be shredded documents, amid tight security and heavy media scrutiny.
The diplomatic staff have until tomorrow to vacate the premises.
On Friday, Beijing ordered the closure of the US consulate in a tit-for-tat move after Washington ordered the Chinese consulate in Houston, Texas, to shut.
China described its decision as a "legitimate and necessary" response to "unreasonable" US action.
Workers could be seen removing black trash bags - one of which split to show shredded paper in it - from the Chengdu consulate compound.
Staff could also be seen moving around inside, AFP news agency reported, and the US insignia was removed from within the compound.
Outside, the police had closed off the street to pedestrians. Many people who were walking on the other side of the road stopped to take pictures before moving on.
Chinese state media provided a blow-by-blow account of every development, and a live stream from outside the consulate, which began on Friday, had attracted 49.5 million viewers by yesterday evening.
In Houston, Chinese consular staff left the building shortly after 4pm local time on Friday (5am Singapore time yesterday), when the closure order took effect.
A group of men who appeared to be US officials were seen forcing open a back door of the consulate, Reuters reported.
After they had gone inside, two uniformed members of the US State Department's Bureau of Diplomatic Security arrived to guard the door.
Beijing said late yesterday that US officials had forced their way into the vacated Chinese consulate.
"China has expressed strong dissatisfaction and firm opposition to the US' forced entry into the Chinese Consulate-General in Houston, and has lodged solemn representations," said Foreign Ministry spokesman Wang Wenbin in a statement, adding that there will be a "proper and necessary response".
Meanwhile, Houston Consul-General Cai Wei posted a lengthy open letter on the consulate's website, looking back on his stint and promising to continue supporting "friendly exchanges" between the Chinese and the American south.
At times nostalgic and hopeful, the letter was a departure from the fiery rhetoric that has become common in US-China interactions in recent months. It was posted only on the Chinese version of the page.
"Although the direction of history is sometimes tortuous due to the interference of a few people, the friendship between the Chinese and American people will not be interrupted, and the bright prospects of friendly cooperation between China and the United States cannot be stopped by anyone," he wrote.
Bilateral ties are in their worst state in years, with the world's two largest economies at odds over a range of issues, including trade, espionage and China's handling of the Covid-19 pandemic.