The Spanish government departments, commonly known as Ministries, are the main bodies through which the Government of Spain exercise its executive authority. They are also the top level of the General State Administration. The ministerial departments and their organization are created by Royal Decree signed by the Monarch and the Prime Minister and all of them are headed by a Cabinet member called Minister.

The Office of the Prime Minister, officially Presidency of the Government is the Spanish government structure that groups all the departments and officials that are at the service of the prime minister to fulfil its constitutional duties. It is staffed by a mix of career civil servants and advisers. The highest-ranking official within the Office is the Chief of Staff, which is a political appointment on which the rest of the Office officials depend.