Mauritania votes to change constitution despite widespread protests
The planned changes will also change the country's flag and national anthem - if the second chamber also votes in favour of the changes to abolish itself.
Only six MPs out of a total of 147 did not vote for the motion, which may be put to a referendum.
The vote was initially delayed after a number of opposition MPs voiced their protests to the vote.
The opposition party claims that the changes to the constitution will place the country in crisis and do not help the majority of the country's population who are living in poverty.
President Mohammed Ould Abdel Aziz said in October that the constitutional change must be put to a referendum before it can be approved.
A previous version of the change to the constitution had allowed the president to stand for a third term, but this was quashed by opposition protests.
"This question has to come to an end. I am telling you the term limits will not be changed," said Abdel Aziz.
Thousands of people demonstrated against the proposed constitutional amendments in the country's second city, Nouadhibou, chanting slogans against government manipulation and corruption.
Two senior members of the country's opposition were also arrested in the protests on Thursday.
The new flag will add two bands of red to the top and bottom of the old flag, symbolising "the efforts and sacrifices" the Mauritanian people will sustain to defend their country.