Kimberly Sue Endicott was travelling in a auto on Tuesday on an evening game drive with Remezo and two other tourists in the national park when four men held them at gunpoint.
Kimberly Sue Endicott, 56, an aesthetician from Costa Mesa, California, and her driver, Congolese national Jean-Paul Mirenge Remezo, were rescued by security forces, the Ugandan government said on Twitter.
Check back for updates on this developing story. The captures had demanded a $500,000 ransom, but it was not immediately clear how much of that was paid or by who. The driver was identified as "senior guide" Jean Paul. The two were found at Ishasha in western Uganda near its border with the Democratic Republic of Congo.
The two were abducted at gunpoint while on a game drive on Tuesday evening, the Ugandan Tourism Board and Ugandan police said in a statement.
Police said the incident occurred between 6pm and 7pm, along the Edward track, a section located between Katoke gate and wilderness camp.
President Donald Trump tweeted that the pair had been released and added, "God bless them and their families!"
Queen Elizabeth National Park runs along part of the country's border with DR Congo.
Uganda recorded a surge in kidnapping cases previous year, prompting street protests by activists who said security agencies weren't doing enough to protect residents. "Even a small payment to a group in, say, Africa can facilitate the killing or seizure of tens or even hundreds of others, including Americans or foreign nationals in that region".