With 96 MPs voting in favour and 26 against, the parliamentary decision effectively adds three more years to Lahud's presidency.
The outcome of the vote on Friday is seen as an outright rejection of Thursday's UN resolution.
The resolution had been sponsored by the US and France, who argued the plan to extend Lahud's term was the result of Syrian interference in Lebanon.
The UN vote was slammed by Lebanese and Syrian officials.
Lebanese Foreign Minister Jean Ubaid said on Friday the resolution was "improper" interference in Lebanon's internal affairs.
The Syrian government is under
fire for its Lebanon presence
"We believe that the principles and political, economic and security facets of these relations [with Syria] constitute an issue of sovereignty that complies with UN legitimacy and secures for Lebanon various benefits, interests and guarantees," he said.
One Syrian diplomat who spoke to Aljazeera.net on the condition of anonymity, described the resolution as "unprecedented".
"There is no justification for this. It is interference in internal Lebanese affairs. Usually when the Security Council meets it is for an international crisis, but they are getting involved in the legitimate relationship between two states," the diplomat said.
Damascus and Beirut signed a friendship pact in 1991 that sought to coordinate foreign and security policy between the two states, formalising the presence of Syrian troops in Lebanon.
The diplomat accused the Security Council of "double standards", arguing that the council should address the Israeli occupation of Palestinian territories.
The Security Council voted 9-0 with six abstentions - the minimum vote possible - to adopt the resolution after the US and France agreed under pressure not to mention Syria by name.
Syrian forces entered Lebanon in 1976, initially to protect the Christian community in the 1975-1990 civil war. Later, Damascus viewed its presence there as a force for stability as the country recovered from the bloody conflict.
A Lebanese affair
The resolution elicited a lukewarm response in Lebanon, with many saying the involvement of the UN would have negative consequences.
"I don't think we need now the UN to help us in Lebanon. It will poison the relations between Lebanese," said MP Walid Jumblat, who is spearheading an effort by opposition MPs to stop the extension of Lahud's term.
"Respecting the constitution is a purely Lebanese affair," Jumblat told Aljazeera.net.
"They have asked impossible things to be achieved such as the dismantling of Hizb Allah"
Opposition MP Walid Jumblat
"They have asked impossible things to be achieved such as the dismantling of Hizb Allah."
In addition to calling for a withdrawal of "foreign forces" from Lebanon, the resolution also asks "all Lebanese and non-Lebanese militias" to disband, a veiled reference to the Shia resistance group Hizb Allah.
Lebanese legal expert Chibli Mallat echoed Jumblat's concerns.
"I am worried about what the resolution will do to the region," Mallat told Aljazeera.net.
"This is a process in Lebanon that has been hijacked unnecessarily and the consequences will be very difficult to reverse."
The UN resolution comes at a time when there is mounting pressure on Syria. Israel has accused Hamas leaders who reside in Syria of ordering Tuesday's suicide attack in Beir al-Saba and has threatened Syria with military action.
Rime Allaf, Syria analyst with the British Royal Institute for International Affairs, said the resolution was part of a US attempt to isolate Syria in the region.
"Basically the Americans are trying to get Syria out of the picture," Allaf told Aljazeera.net.
"Basically the Americans are trying to get Syria out of the picture"
Rime Allaf, Syria analyst
She said recent Syrian calls to reopen negotiations on the Israeli-occupied Golan Heights have been ignored by Washington.
"This has made it clear to the Syrians that they will not be included in negotiations on the region," she said.
Allaf said the Bush administration knows that its demands on Syria to curb Hizb Allah and Palestinian groups cannot be met by Syria, as these groups are vital to Syrian policy in the region.
But Allaf said the Syrians had been "naive" in underestimating the international response to the decision on extending Lahud's term.
"It's a severe miscalculation that they made while trying to maintain their trump card which is Lebanon," she said.
"What the Syrians did not calculate is that the EU would be so willing to align itself with the US."