The amendment to the electoral law would prevent dozens of opposition figures, including jailed former MP Mussallam al-Barrak, from standing in next year's election.
The amendment was supported by 40 deputies, including all cabinet ministers present, and opposed by just three.
It will pass into law once the cabinet endorses the change and publishes it in the official gazette.
The amendment states that "people convicted in a final court ruling of insulting God, the prophets and the emir are barred from elections."
In the past few years, courts handed down various jail terms against opposition activists for insulting the emir, Sheikh Sabah al-Ahmad al-Sabah, or undermining his authority.
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Barrak, secretary general of the nationalist Popular Action Movement, is serving his second year in jail after he was convicted of insulting the emir in a speech at a public rally in 2012.
The amendment also comes after several figures and groups, including the Muslim Brotherhood-linked Islamic Constitutional Movement, the largest opposition group, decided to end their four-year election boycott.
A broad alliance of Islamist, nationalist and liberal opposition groups boycotted two general polls in 2012 and 2013 in protest at a change in electoral law.
The opposition alliance said at the time that the change, brought unilaterally by authorities but later endorsed by Kuwait's top court, would allow the government to control parliament.
The opposition held massive street protests in 2011 and 2012 demanding democratic reforms and an elected government.
But in the past two years, the strength of the opposition alliance, which last controlled parliament in 2012, weakened considerably as the groups became fragmented.