| 3 May Constitution Day | |
|---|---|
 3 May Constitution, by Matejko. King Stanisław II Augustus (left) enters St. John's Cathedral, where deputies will swear to uphold the Constitution. | |
| Official name | Święto Konstytucji 3 Maja |
| Observed by | Poland |
| Type | national, secular, patriotic |
| Significance | Enactment of the 3 May Constitution in 1791 |
| Celebrations | Parades |
| Date | 3 May |
| Frequency | annual |
3 May Constitution Day (also 3rd May National Holiday; Polish: Święto Konstytucji 3 Maja) is a Polish national and public holiday that takes place on 3 May. The holiday celebrates the declaration of the Constitution of 3 May 1791 – the first modern constitution in Europe. Festivities date back to the Duchy of Warsaw early in the 19th century, but it became an official holiday only in 1919 in the Second Polish Republic. Delisted during the times of the Polish People's Republic, it was reestablished after the fall of communism in modern Poland.