Mr Trump has called the president the worst in history, while Mr Obama said the Republican was unfit for the office.
The New York hotel developer, now president-elect, persistently questioned the birth legitimacy of the Hawaii-born president, and was publicly mocked for it by Mr Obama.
The two men spoke for more than an hour in the Oval Office on Thursday and when they emerged, they tried to put their bitter past behind them, speaking warmly about unity and a peaceful transition.
But the cameras told another story.
When Donald Trump met President Barack Obama at the White House, their antipathy was barely concealed.