In a statement, Facebook said the 48 adverts had violated the site’s policies on voter interference, but did not provide more details to Business Insider, who reported on the clamp-down.
Mr Trump has maintained that the 2020 presidential election would be the "most inaccurate and fraudulent in history", in part due to increases in mail-in ballots amid the pandemic.
Those claims, despite being baseless, have been seen to delegitimize both election processes and the outcome on 3 November.
According to a JL Partners-Independent survey published last week, around two-thirds of American voters said they were “very or quite” concerned that the election will not be free or fair, when polled on the matter.
The Trump campaign ads, which were aimed at those who had not cast ballots in next week’s election, were reported to have been seen by people who had already voted, raising concerns about attempts to undermine the integrity of the election.
Accompanied by videos showing the president praising his Supreme Court nominee, Amy Coney Barrett, voters were told that Mr Trump needed “you to take action”.
"Your vote has not been counted. This is the fight for our future,” read the adverts. “President Trump needs you to take action, and vote. We need you to vote early."
Another version with the same text, but with the sentences rearranged, still included the phrase "your vote has not been counted," reported Business Insider.
Some 399,000 people saw the adverts, which come despite Mr Trump’s attacks on early voting by mail-in ballots during the pandemic.
Some 58 million ballots have already been cast in the 2020 election, according to the Associated Press - surpassing the total number of early ballots four years ago.
Democrat-registered voters have accounted for 51 per cent of all ballots cast so far, compared to 31 per cent for Republicans.