The social media giant’s CEO stopped following the outgoing president over the weekend, according to reports.
Mr Dorsey also unfollowed first daughter Ivanka Trump, President-elect Joe Biden and Vice President-elect Kamala Harris, according to @bigtechalert, which tracks Silicon Valley leaders on Twitter.
Mr Trump has been a dominant figure on the platform since entering the White House, tweeting more than 56,000 times and has amassed 88.5 million followers.
But the president has lost 371,057 followers since 17 November, according to Factba.se, a website that tracks his tweets and public statements.
However, Mr Biden has gained 2,594,809 followers in the same time period, and now has a total of 21.6 million.
A Twitter spokesperson declined to comment.
During the election campaign the company has added warnings and misinformation labels to Mr Trump’s tweets that break its rules.
The company has admitted giving Mr Trump more leeway than other users while he is president.