The court’s eight-member panel reached the unanimous decision 92 days after lawmakers voted to oust Park on power abuse charges. At least six justices were required to uphold the impeachment.
“The president's violations of the Constitution and the law amount to a betrayal of the people's trust and are grave actions that cannot be tolerated from the perspective of defending the Constitution," acting Chief Justice Lee Jung-mi said as she read out the verdict in a televised statement.
Supporters of the president responded with violent protests, during which two members of the public were killed and several others injured according to police. Nearly 22,000 officers were deployed to guard demonstration hotspots amid the continuation of anti-Park rallies that have involved millions of people since last year.
Park was caught up in a wide-ranging scandal in October when suspicions arose that she had allowed a private confidante -- Choi Soon-sil -- to influence state affairs.
While Park has been protected from prosecution by her position until now, Choi is among dozens of suspects who have been indicted over their connection to allegations ranging from bribery to the creation of a cultural blacklist.
Friday’s ruling condemned the president for “thoroughly hiding” Choi’s role, which was sufficient to ensure her ousting as other charges fell short, such as the claim Park neglected her duty to protect victims of the 2014 Sewol ferry disaster, which claimed 304 lives.
Prosecutors are still expected to interrogate Park to establish how closely related she was to presidential office corruption, including Samsung’s suspected bribes worth tens of millions of dollars to ensure government support for a merger in 2015.
Meanwhile, Prime Minister Hwang Kyo-ahn will continue to act as president with the country preparing for a snap election within 60 days.
Park herself remained silent Friday and is temporarily being allowed to stay at her official residence.