Sauli Niinisto had to explain to the US leader that the reporter he chose to take a question from was not the same journalist who had asked a question previously.
The gaffe came after the US President prompted his guest to pick a reporter to receive a question from but was left asking “again?” when Mr Niinisto made his choice.
“You’re going to give [it to] her – the same one?” Mr Trump asked before the Finnish leader snapped back.
To the amusement of the two women, Mr Niinisto replied: “No, she is not the same lady.”
President laughed off the mix-up as one of the women added: “We have a lot of blonde women in Finland.”
The journalists in question later tweeted about their eventful day at the White House.
“My 15 minutes of fame :),” wrote Maria Annala, while Paula Vilén added: “Hectic but inspiring day at the WH.”
The awkward exchange with the press follows another in which the billionaire tycoon interrupted a phone call with Irish Prime Minister Leo Varadkar to compliment an Irish journalist who was in the room at the same time.
Donald Trump told the Taoiseach: “Well, we have a lot of your Irish press watching us.”
The US leader then pointed to RTÉ journalist Caitriona Perry, who was in the room, and called her over to speak to him.
“Where are you from? We have all of this beautiful Irish press,” he said.
“She had a nice smile on her face so I bet she treats you well,” the President then told Irish leader.