The Party of the Third Age (Luxembourgish: Partei vum 3. Alter, French: Parti du Troisième Âge) was a political party in Luxembourg. It contested the 1999 election to the Chamber of Deputies, but has since disbanded.

Its party platform was dedicated to pensioners' issues, and its name is a reference to its core constituency.^[1] In its only legislative election in which it stood candidates, in 1999, it contested only the Sud constituency, in which it came eighth and last, with 0.4% of the vote. It folded soon afterwards.