The Districts of Portugal (Portuguese: Distritos de Portugal) are the most important first-level administrative subdivisions of continental Portugal. Currently, mainland Portugal is divided into 18 districts.

As an administrative division, each district serves mainly as the area of jurisdiction of a civil governor, who acts as the local delegate of the Central Government of Portugal.

The Districts of Portugal were established by a royal decree of 18 July 1835. On the Portuguese mainland, they correspond to the current districts, with the exception of Setúbal District, which is the result of a split of Lisbon District in 1926. This decree did not affect the then extensive colonial empire.

The 1976 Portuguese Constitution specifies that Portugal has only, as first-level divisions, the autonomous regions (Azores and Madeira) and the administrative regions (to be created in mainland Portugal). According to the Constitution, the districts shall be disestablished in territories in which an autonomous or administrative region has been created.

The districts were abolished in Azores and Madeira in 1976, when the autonomous regions were created. In 1998, a proposal was submitted to referendum to create eight administrative regions in mainland Portugal, and so to extinguish the districts. The proposal was rejected at the ballot box and so the districts continued to exist in mainland Portugal. Despite their abolition in the autonomous regions, the areas of the three former districts of Azores are still used as areas of jurisdiction of some government and non-government entities, like the district finance directorates (Tax Authority regional offices) and the district football championships.

However, the importance of the districts has been decreasing. In recent years, some administrative, financial and political competencies have been delivered to the CCDRs (Comissão de Coordenação e Desenvolvimento Regional, English: Commission for Regional Coordination and Development) and to the municipalities, to the detriment of the districts. In 2003, the Portuguese municipalities were allowed to organize themselves into intermunicipal communities (comunidades intermunicipais) and metropolitan areas (áreas metropolitanas), which allowed for a lessening in the importance of the districts.

Also, the abolition of the districts is a subject that returned to discussion in Portuguese society. In 2009, during the campaign for the legislative election of 2009, the leader of the Socialist Party, José Sócrates, promised a new referendum to the administrative regions and therefore, the abolition of districts, if he won the election. Other personalities support the creation of administrative regions and therefore the abolition of districts.

Despite being in the process of being phased out by the decentralisation policies of the government, the districts still remain the most relevant subdivision in the country by serving as a basis for a series of administrative divisions such as electoral constituencies, police, and civil protection regional commands; sports district associations; and championships.