For the constitution of the Grand Duchy of Finland see: Swedish Constitution of 1772

The Constitution of Finland ( or ) is the supreme source of national law of Finland. It defines the basis, structures and organisation of government, the relationship between the different constitutional organs, and lays out the fundamental rights of Finnish citizens. The original Constitution Act was enacted in 1919, soon after Finland declared its Independence in 1917, but the current Constitution came into force on 1 March 2000.