Prosecutors have ordered the ousted president to appear before them on Tuesday next week for questioning over the corruption scandal that triggered her dramatic downfall.
A criminal suspect in the scandal, Park had repeatedly refused to make herself available for questioning by the prosecutors before the country's highest court confirmed a parliamentary impeachment motion against her.
The protest against the impeachment saw 2,000 of her supporters walking slowly, waving banners and national flags, including a huge one carried by some 100 people.
They followed a black funeral limousine decorated with national flags.
More From This Section
The corruption and influence-peddling scandal is centred on Park's close confidante Choi Soon-Sil, who is on trial for abuse of power and coercion.
Choi is accused of using her presidential ties to force local firms including Samsung to "donate" nearly USD 70 million to non-profit foundations she allegedly used for personal gain.
Park -- the 65-year-old daughter of the late former strongman Park Chung-Hee -- has been named as Choi's accomplice who helped her extract money from the firms.
Park has voiced defiance over the court ruling, saying "the truth will eventually be revealed".