Politics in Portugal operates as a unitary multi-party semi-presidential representative democratic republic, whereby the Prime Minister of Portugal is the head of government, and the President of Portugal is the non-executive head of state with several significant political powers they exercise often. Executive power is exercised by the Government, whose leader is the prime minister. Legislative power is primarily vested in the Assembly of the Republic, although the government is also able to legislate on certain matters. The Judiciary of Portugal is independent of the executive and the legislature. The President exerts a sort of "moderating power", not easily classified into any of the traditional three branches of government.

The president of Portugal, officially the president of the Portuguese Republic, is the head of state and highest office of Portugal.