Hiến pháp năm XII

The Constitution of the Year XII (French: Constitution de l’an XII), also called the Organic Sénatus-consulte of 28 Floréal, year XII (Sénatus-consulte organique du 28 floréal an XII), was a national constitution of the French First Republic adopted during the Year XII of the French Revolutionary Calendar (1804 in the Gregorian calendar).

It amended the earlier Constitution of the Year VIII and Constitution of the Year X, establishing the First French Empire with Napoleon Bonaparte — previously First Consul for Life, with wide-ranging powers – as Napoleon I, Emperor of the French. The Constitution established the House of Bonaparte as France's imperial dynasty, making the throne hereditary in Napoleon's family. The Constitution of the Year XII was later itself extensively amended by the Additional Act and definitively abolished with the final return of the Bourbons in 1815.

This text of 142 articles founded a new regime, the First Empire, and adapted the old institutions to this regime.