"We have formally charged Park... with multiple offences including abuse of power, coercion, bribery and leaking state secrets," they said after wrapping up the months-long investigation.
Park is accused of colluding with her confidante Choi Soon-sil, who is already on trial, in coercing local conglomerates into donating a total of 77.4 billion won ($68 million) to two non-profit foundations.
Choi allegedly used some of the donations for personal gain.
Park is also accused of offering policy favours to top businessmen who enriched Choi, including Samsung heir Lee Jae-Yong who was arrested earlier and is also on trial for bribery.
Prosecutors on Monday also charged Shin Dong-Bin, the chairman of the giant Lotte Group, with bribing Choi and Park.
Park, 65, has been behind bars at at a detention centre in the outskirts of Seoul since her arrest last month.
The scandal prompted millions to take to the street for weeks calling for the ousting of the conservative president. Parliament impeached Park last December amid growing public pressure.