Cemil Cicek, a government spokesman, said on Monday that parliament will convene to debate the deployment this week or next.
Cicek said: "In principle, we've decided to join the UN peacekeeping mission.
"The issue was debated in detail, considering our country's national interests. We will call on the parliament to meet in the shortest time."
The cabinet's decision comes amid mounting opposition in Turkey to a deployment.
Ahmet Necdet Sezer, Turkey's president, who holds a ceremonial post but wields considerable influence in the country, has come out strongly against the deployment.
On Friday Sezer said it was not Turkey's "responsibility to protect the interests of other countries".
Several legislators within the ruling Justice and Development Party have also spoken out against a possible deployment.
But the United States, the European Union and Israel have been pressing Turkey, the only Muslim member of Nato and a country with close ties to Israel and Arab countries, to send peacekeepers.
Turkey ruled Lebanon for about 400 years during the Ottoman Empire and many Turkish officials are keen for their country to have a say in an area that they regard as Turkey's back yard.
Italy has also given the final go-ahead to deploying 2,500 troops in southern Lebanon.
"If, as we expect, the contingent manages to leave tomorrow morning, it will be operational on September 1," Arturo Parisis, Italy's defence minister, said.
Bulgaria said it would probably send "around a hundred" soldiers to Lebanon, said Ivaylo Kalfin, the foreign minister, on Monday.
Romania said on Monday that it would not contribute any troops towards the force.