Massie lost his party's primary in his home state on Wednesday night and thus has no chance of being re-elected in the midterm elections in November.
The Republican nominee will instead be former elite soldier Ed Gallrein, who had Trump's support.
Gallrein's victory, in what media outlets describe as the most expensive primary campaign to date, is seen as a major triumph for the president. Trump has repeatedly described Massie, who has served in the House of Representatives since 2012, as "an idiot."
In his concession speech, Libertarian Massie hinted that he may be interested in the 2028 presidential election.
"We'll talk about it later," he said, according to the AP.
