Hearings have proceeded without Park, who refuses to testify. The Supreme Court cannot force the president to attend.
South Korea's parliament voted to impeach President Park in December after hundreds of thousands of protesters took to the streets for weeks demanding her removal.
Park is accused of being part of a corruption scheme involving longtime confidante Choi Soon-sil, a woman who allegedly extorted tens of millions of dollars from various companies in the guise of donations, later funneling these funds into questionable foundations.
Choi is also charged with exerting undue influence on the country's government. Prosecutors have also indicted Choi's niece as well as several former officials in the case.
Mass protests across South Korea resulted in the impeachment vote - which now has to be ratified - or rejected - by the Supreme Court
The National Assembly, which must have its vote upheld by the Constitutional Court for the impeachment to take effect, accused Park of a serious breach of the constitution during the first full hearing.
The country's top court has six months to decide if she should be removed from office or reinstated.
On Thursday, the chief prosecutor in the case said that Park had abused her position by "broadly and gravely" violating the constitution to commit corruption and turn state affairs into a profit tool for her friend.
Park's lawyers meanwhile argue that there is no evidence to back the corruption allegations.
During the hearings, Seo Seok-gu, a lawyer representing Park, argued that the investigation was biased, suggesting that the protests that led lawmakers to impeach the president had been influenced by groups sympathetic to North Korea. The lawyer went as far as to comparing the allegations against Park's to the trial of Jesus Christ.
Park has rejected the accusations of misconduct.
New presidential vote in 2017 regardless of trial outcome
The Constitutional Court's initial hearing on January 3 was cut short after Park failed to attend. It was decided, however, that proceedings would continue on January 5 regardless of her presence. The failure of a number of Park aides to appear for testimony also slowed the proceedings.
Park has apologized for her behavior, claiming that she only wanted to gauge public opinion through her close relationship to her aid, Choi Soon-sil
South Korea is due to hold elections by the end of 2017. However, if Park is removed from office, South Korea must hold an election within 60 days.
South Korean Prime Minister Hwang Kyo-ahn is filling in as Acting President in the meantime, until the Supreme Court reaches its verdict.
Some people have suggested that former UN Secretary-General Ban Ki-moon, a former South Korean foreign minister, could be a candidate for the presidency.
ss/kms (AP, AFP)