The 38-year-old head of the legislature, Jose Jeri, assumed the South American country's presidency shortly after the vote, telling lawmakers he would lead a transitional government until elections in April 2026.
After being sworn in, Jeri vowed to spend the remainder of the presidential term cracking down on spiralling violence.
"The main enemy is outside, in the streets -- the criminal gangs, the crime groups... we must declare war on them," he said.
Boluarte's ousting is the latest in a string of political upsets for Peru, which has had seven presidents in the past nine years.
Citing Boluarte's "permanent moral incapacity", Congress kicked the lightning swift impeachment proceedings into motion late Thursday, garnering support from across the political spectrum, including parties once loyal to her.
The lawmakers summoned Boluarte to appear before Congress at 11:30 pm (0430 GMT Friday), but she skipped the proceedings, which ended moments later with 122 votes to impeach her, according to an updated count announced by the legislature.
The ousted president's lawyer, Juan Carlos Portugal, argued she was granted too little time to prepare, obstructing "due process".
Outside parliament in the capital Lima, dozens of people gathered to celebrate Boluarte's dismissal, an AFP correspondent said.
"Down with Dina," read a sign held by one of the protestors.
Congresswoman Norma Yarrow, of right-wing party Popular Renewal, said that "the country has been mistreated by the cabinet and the president. Extortion and crime have increased... she deserves punishment."
AzVision.az
More about: Peru
