He said that about 1,500 to 2,000 ISIS fighters remain in a 20-square-mile pocket in Syria near the Iraqi border.
Votel praises efforts by Iraq's security forces and a USA -backed coalition of Syrian fighters known as the Syrian Democratic Force.
The amendment called on the Trump administration to certify conditions had been met for the groups' "enduring defeat" before any significant withdrawal from Syria or Afghanistan.
Trump's decision to leave Syria, which he initially said would be rapid but later slowed down, shocked U.S. allies led to the resignations of Defense Secretary Jim Mattis and the top envoy to the anti-Islamic State coalition, Brett McGurk.
ISIS "remains a potent force of battle-hardened and well-disciplined fighters that could likely resurge in Syria absent continued counterterrorism pressure", the report from the inspector general said.
Trump's decision to leave Syria, which he initially said would be rapid but later slowed down, shocked US allies led to the resignations of Defence Secretary Jim Mattis and the top envoy to the anti-ISIS coalition, Brett McGurk.
Members of the Republican-controlled chamber voted 70-26 in favor of a non-binding amendment sponsored by Majority Leader Mitch McConnell contending that the Islamic State and al-Qai'da still pose serious threats to US interests.
At nearly the same time the report was released, the US Senate was approving an amendment critical of Mr Trump's Syrian and Afghanistan withdrawal. There have been no reports to date of US troops leaving Syria.
The move is the latest blow to President Trump after lawmakers passed other symbolic motions denouncing US support for the Saudi-led military intervention in Yemen and calling for sanctions to be imposed on Riyadh due to the involvement of Crown Prince Mohammad bin Salman in the murder of journalist Jamal Khashoggi.More news: European allies recognise Juah Guiado as Venezuelan president
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Trump said in a weekend interview that the caliphate is "almost knocked out".
He gave the committee assurances that the US will seek to protect the USA -backed Syrian Democratic Forces, who have led the fight against ISIS in Syria, and the Syrian-Kurdish fighters within the SDF.
In December, Trump tweeted, "We have defeated ISIS in Syria, my only reason for being there during the Trump presidency".
The Defence Department watchdog report warned that even with the ISIS forces on the run, the militant group "is still able to co-ordinate offensives and counter-offensives, as well as operate as a decentralized insurgency".
A report by United Nations Secretary-General Antonio Guterres warned that Islamic State has transformed into a covert network, including in its strongholds of Syria and Iraq, but is still a threat with centralized leadership, up to $300 million at its disposal and thousands of fighters.
He added the planning for a withdrawal includes devising ways to keep pressure on ISIS, but he declined to discuss strategies in an unclassified setting.
Trump's Syria withdrawal has also fueled rare, vocal opposition from within his own Republican party.
According to the report, U.S. Central Command believes that ISIS fighters will continue to conduct "opportunistic attacks" on U.S. troops as they withdraw.
Trump is expected to speak to the gathered foreign ministers at the U.S. State Department-hosted conference on Wednesday is widely expected to reiterate and expand on his anti-ISIS message from the State of the Union, officials said.