Focus on crackdown
The debate that began on Monday aimed to focus attention on tough measures used to break up the so-called red shirt protests on May 19.
The opposition also accused Abhisit and the five ministers of corruption and economic mismanagement.
The no-confidence motion was led by the Puea Thai Party linked to Thaksin Shinawatra, the prime minister ousted in a 2006 coup, whom Abhisit's government accuses of instigating the weeks-long protests that paralysed the capital's high-end commercial district.
Puea Thai legislators said excessive and illegal measures, such as night-time operations and the use of live ammunition, were used by troops in attempts to surround two protest sites and disperse demonstrators, leaving nearly 90 people dead and around 1,500 injured.
Ahead of the debate, Navi Pillay, the UN human rights chief, said an independent investigation into the violence was necessary to "foster longer-term political reconciliation" in Thailand.
"I urge the government to ensure that an independent investigation of recent events be conducted and all those found responsible for human rights violations are held to account," Pillay told a meeting of the UN Human Rights Council on Monday.
Reacting to Pillay's call, Sihasak Phuangketkeow, the Thai ambassador to the UN, said "the Thai government is open to scrutiny and is ready to be subject to legal process in accordance with the law", adding that the army had acted in line with international standards.
The government lifted a night-time curfew on Saturday, saying the situation was returning to normal, but it left in place emergency rule across more than one third of the country, including Bangkok.