The move, spearheaded by a coalition of far-right and leftist lawmakers, marks France’s first successful no-confidence motion in more than six decades.
The measure, passed in the National Assembly with 331 votes, well above the 288 needed for a majority, brings an abrupt end to Mr Barnier’s three-month tenure, the shortest of any government in France’s Fifth Republic.
The vote was catalysed by widespread opposition to his controversial social security reforms, which he had pushed through by presidential decree earlier this week after failing to secure sufficient parliamentary support.
French politician Marine Le Pen’s far-right National Rally, alongside the leftist coalition, united in opposition to Mr Barnier’s approach, ultimately leading to his removal.
According to the BBC, the RN leader described the budget as “toxic for the French.”
Mr Barnier told the National Assembly that voting him out of office would not solve the country’s financial problems. “We have reached a moment of truth, of responsibility,” he said.
The vote has created a tough situation for President Emmanuel Macron, forcing him to choose a new prime minister while managing the political tensions it has caused.
Although Mr Barnier is expected to tender his resignation imminently, he is likely to remain in a caretaker role until Mr Macron announces his replacement.