According to at least one report from social media, the budget was passed through the support of voices and not a head count.
The budget was originally due in November but was not handed down by the dominant O'Neill-Namah coalition until December 6.
There were further delays after the political standoff following the Supreme Court decision which ruled Sir Michael Somare was PNG's rightful prime minister.
While the faction led by MP-elected Prime Minister Peter O'Neill typically commands at least 70 of the 109 seats, there were an estimated 64 parliamentary members present to pass the budget yesterday.
In other important matters, passed in Parliament this week were the first and second readings of the bill to establish a sovereign wealth fund to manage PNG LNG project government revenues from 2014, according to Radio New Zealand.
But the second-round vote to allow a bill to reserve 22 seats for women in the 2012 election did not pass this week, as it received only 67 of the 73 votes required.
It is seen as the last major piece of legislation to be implemented and the bill is also supported by the Somare camp, so there is a prospect it will be passed in coming months.
Of the Somare-aligned MPs, only Dame Carol Kidu has attended Parliament since the Supreme Court outcome.
Kidu, who will not contest the next election, was there on Monday for the vote on the women's bill and copped a barrage of jibes from the O'Neill faction.
But she had no problems shouting over the various heckles she received.
"Shame, you blame us for corruption but have a look at yourself," Kidu reportedly said, according to the Sydney Morning Herald.
In yet another attempt to tinker with PNG's constitution to suit the O'Neill faction's own ends, it passed an amendment enforcing an age limit of 72 for the office of PM.
Somare is 75.
The move was criticised by former PM and Public Services Minister Bart Philemon, who broke ranks with the O'Neill faction as a consequence, according to a separate report by Radio New Zealand.
Philemon reportedly said the law was wrong and made in a panic to "derail the due process in the constitution".
While the next election is scheduled for June, there could be a further political crisis around February when the Supreme Court is expected to restart contempt of court proceedings against key MPs of the O'Neill coalition.