Czech deputies on Tuesday voted a no-confidence motion against Prime Minister Mirek Topolanek, whose government holds the rotating European Union presidency.
The official count showed the motion gained the 101 votes in the 200-seat lower chamber required to topple the governmment.
Following the vote, Topolanek said he would resign.
"I will behave exactly in line with the constitution," he said.
The constitution says the government must resign after it loses confidence in parliament.