"We dismiss the defendant President Park", Justice Lee Jung-mi said at the time.
Ms Park's dismissal from office means South Korea must now elect a new president by early May.
While she is the first South Korean president to be successfully ousted, she was the second to face impeachment. The court's decision strips Park Geun-hye of her immunity from criminal prosecution, which will force her to undergo interrogation by prosecutors over her alleged crimes.
Sensing history, thousands of people - Park supporters, many of them dressed in army-style fatigues and wearing red berets, and those who wanted Park gone - gathered around the Constitutional Court building and a huge public square in downtown Seoul to watch the verdict live on a big television screen.
An independent investigator claims the former president was an accomplice to Choi in attempting to extract 43bn won (£30.9m) from the technology giant, saying the two friends "shared economic interests", the Korea Herald reports.
Park's removal from office has sparked a snap presidential election, which is expected to take place as soon as May.More news: AJ Bouye tells the Texans he is signing elsewhere
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The main opposition Democratic Party of Korea is home to several top candidates in recent polls, including frontrunner Moon Jae-in.
Relations with China and the United States could dominate the presidential campaign, after South Korea this month began deployment of the U.S. THAAD missile defense system in response to North Korea's stepped up missile and nuclear tests.
Park becomes South Korea's first democratically elected leader to be forced from office, capping months of paralysis and turmoil over a corruption scandal that also landed the head of the Samsung conglomerate in jail. Questions have also been raised about her influence over key policy decisions.
"The fierce actions of the people from all walks of life in South Korea have passed death sentence on the traitor, an eruption of the pent-up wrath and anger at her group of traitors". However, Park Geun-hye has apologised but denied any wrongdoing.
He called on Park Geun-hye's supporters and opponents to put aside their differences to prevent deeper division. Nostalgia for her father's conservative rule led her a sweeping electoral victory in 2012.
Park, who didn't appear in court Friday, is accused of allowing long-term family adviser Choi to meddle in state affairs as well as accepting a payment of $38 million from Samsung to smooth the process of a controversial merger of two of its biggest affiliates. Lee, who is facing trial, is another potent sign that the old order is not holding.