The mandate allows the use of the armed forces in the neighbouring countries as well as for foreign forces to transit Turkish territory in operations against Islamic State (IS) jihadists.
In the 550-seat chamber, 298 deputies voted in favour and 98 against, with the big majority of the ruling Justice and Development Party (AKP) meaning the outcome was never in doubt.
The vote came after President Recep Tayyip Erdogan last week indicated Turkey was shifting its policy to take a more active role in the fight against IS militants, who have advanced to within a few kilometres (miles) of the Turkish border in northern Syria.
But the mandate approved by parliament -- which lasts for one year -- is very broad in scope and in no way commits Turkey to sending armed troops into Syria and Iraq.
The government has said it will decide on concrete steps after winning authorisation, with many analysts expecting a cautious approach.
"You shouldn't expect any move immediately after the mandate" is approved, Defence Minister Ismet Yilmaz told reporters before the parliament session.
The opposition Nationalist Movement Party (MHP) also voted in favour but the main opposition Republican People's Party (CHP) and pro-Kurdish People's Democratic Party (HDP) voted against.
The United States is pressing Ankara for the use of its Incirlik air base in the Adana region of southern Turkey to allow US jets to launch assaults against IS in Syria.
But it is unclear if Turkey will allow the transit of lethal weaponry and it may limit the authorisation to humanitarian aid and non-lethal supplies.
Whether the Turkish armed forces will ever be used against IS militants is also highly questionable.
Erdogan has called for a buffer zone inside Syrian territory backed by a no-fly zone but it is unclear how this could be implemented.
He has said "dropping tons of bombs" alone -- a reference to US air strikes -- will not solve Syria's problems and a long-term solution for the country is needed.
- 'Turkey won't close its eyes' -
Turkey has until now been bitterly criticised in some quarters for not doing enough to stem the flow of jihadists across its territory and has even been accused of colluding with IS.
In a policy spearheaded by then foreign minister, now Prime Minister, Ahmet Davutoglu, Turkey supported Islamist-tinted rebel groups in Syria in the hope they would overthrow President Bashar al-Assad.
"The expansionist and pan-Islamist policy of Prime Minister Davutoglu can only lead Turkey into war," senior CHP lawmaker Mehmet Akif Hamzacebi told the session.
But Yilmaz, addressing parliament to win support for the motion, said that Turkey could "not close its eyes" to the atrocities committed by IS, including beheadings and massacres.
"The only target of this text is a terrorist organisation that wants to disturb the peace" of Iraq and Syria, Yilmaz told parliament.
While Kurds are urging Turkish military action against IS militants, the HDP voted against over concerns the vague wording of the motion could mean the armed forces will be used against Kurdish militants.
Ankara has previously justified its low-key role in the fight against IS by saying its hands were tied by concerns over the fate of dozens of Turkish hostages abducted by IS in Iraq.
But those hostages were freed on September 20 in a reported swap for IS captives held by pro-Ankara Syrian rebels whose details have yet to be fully publicised.