The Republic and Canton of Neuchâtel (French: République et Canton de Neuchâtel; German: Kanton Neuenburg; Romansh: Chantun Neuchâtel; Italian: Cantone di Neuchâtel) is a mostly French-speaking canton in western Switzerland. In 2007, its population was 169,780. The capital is Neuchâtel.

Neuchâtel has a unique history as the only part of present-day Switzerland to enter the Confederation as a principality (on 19 May 1815).

Its first recorded ruler, Rudolph III of Burgundy, mentioned Neuchâtel in his will in 1032. The dynasty of Ulrich count of Fenis (Hasenburg) took over the town and its territories in 1034.