The Constitution of the Commonwealth of Puerto Rico is the document that governs the Commonwealth of Puerto Rico. It is made up of nine articles that detail the structure of the government, as well as the function of several of its institutions. The document is in the Capitol on public display in a glass box. Broad and specific Bill of Rights. As Puerto Rico is an unincorporated territory of the United States, the Constitution of Puerto Rico is compelled to adhere to the postulates of the U.S. Constitution due to the Supremacy Clause, and the pertinent federal legislation regarding the Clause Territorial.

It was ratified by the electorate of Puerto Rico in a referendum on March 3, 1952, also approved by the United States Congress, and promulgated by President Harry S. Truman in an amended version, Public Law 82-447 - 66 Statute 327, on July 3, 1952. On July 10 of the same year, the Constituent Convention of Puerto Rico met again and approved the conditions established by Public Law 82-447. On July 25, 1952, Governor Luis Muñoz Marín proclaimed in a public act the effectiveness of the Constitution and for the first time the flag of Puerto Rico was made in San Juan.

July 25, which had previously been an official holiday in Puerto Rico commemorating the arrival of US troops in Puerto Rico on the same date in 1898, is now known as Constitution Day. According to Professor Antonio Fernós López-Cepero of the University of Puerto Rico, Muñoz Marín chose July 25 for the proclamation of the Constitution with the intention of replacing the celebration of the landing of 1898 with the commemoration of the approval of the Constitution. In an article published on July 25, 2010, the late Professor Fernós López-Cepero stated in an interview with the newspaper El Nuevo Día that he had heard this information from his father, the late Dr. Antonio Fernós Isern, who was the president of the Convention. Constitutional in 2018