The Leader of the Opposition (French: Leader de l'opposition) of the Republic of Mauritius is the Member of Parliament who leads the Official Opposition in Mauritius.

The political party or party alliance which wins the majority of seats in Parliament forms the government and its leader usually becomes the Prime Minister.

The political party or alliance which has the second-largest majority forms the Official Opposition and its leader is normally nominated by the President of the Republic as the Leader of the Opposition.

[1] According to Section 73 of the Constitution of Mauritius, there shall be a Leader of the Opposition who shall be appointed by the President, where the President has occasion to appoint a Leader of the Opposition, he shall in his own deliberate judgment appoint – (a) where there is one opposition party whose numerical strength in the Assembly is greater than the strength of any other opposition party, the member of the Assembly who is the leader in the Assembly of that party; or (b) where there is no such party, the member of the Assembly whose appointment would, in the judgment of the President, be most acceptable to the leaders in the Assembly of the opposition parties:

Provided that, where occasion arises for making an appointment while Parliament is dissolved, a person who was a member of the Assembly immediately before the dissolution may be appointed Leader of the Opposition.