In recent days, anti-Xi posters written in Chinese and English have appeared in several Western universities.
The posters have featured phrases such as “not my president” and “I disagree”.
Criticism of a China’s decision to remove a two-term presidential limit has been heavily censored at home.
The parliament, the National People’s Congress, overwhelmingly passed the constitutional changes on Sunday, as widely expected.
The posters began appearing on some US campuses last week, and were later reported in countries including the UK, France, the Netherlands, Australia and Canada.
A Twitter account @StopXiJinping has been posting links to the posters for download, and encouraging others to join what it calls “our campaign”.
Someone operating the account told the BBC it was being run by Chinese university students and graduates who were living abroad but wished to remain anonymous. The person did not give further details.
“We spoke up as we genuinely believe that Chinese citizens, overseas or at home, have the right to express opinions free from fear,” the account tweeted on Friday.
The phrase “not my president” has been used in other contexts, most prominently by those who oppose US President Donald Trump. (Courtesy BBC)