The governor of Puerto Rico (Spanish: gobernador de Puerto Rico) is the head of government of the Commonwealth of Puerto Rico, an unincorporated territory of the United States. Elected to unlimited four-year terms through popular vote by the residents of the archipelago and island, the governor is the head of the executive branch of the government of Puerto Rico and the commander-in-chief of the Puerto Rico National Guard. Currently, Jenniffer González-Colón is serving as the 190th governor of Puerto Rico.

The governor has a duty to enforce local laws, to convene the Legislative Assembly, the power to either approve or veto bills passed by the Legislative Assembly, to appoint government officers, to appoint justices, and to grant pardons. Since 1948, the governor has been elected by the people of Puerto Rico. Prior to that, the governor was appointed either by the king of Spain (1510–1898) or the president of the United States (1898–1948).

Article IV of the Constitution of Puerto Rico vests the executive power on the governor and empowers them with the faculty to appoint officers. These two faculties in allow the governor to delegate most of their functions while continuing to be the chief executive and head of government.

The first known and recorded heads of government in the history of Puerto Rico were the caciques, the tribal chiefs of the natives known as Taínos that inhabited the island before the arrival of Spaniards. It is believed that the cacique rank was apparently established through democratic means. His importance in the tribe was determined by the size of his tribe rather than his warlord skills, since the Taínos were mostly a pacifist culture. Agüeybaná I is the most-well known cacique as he was the one governing all others when the Spaniards arrived in 1493 although many others existed during his period, as well as before and after him.

When the Spanish Empire colonized Puerto Rico during the 16th century, the Spanish conquistador Juan Ponce de León established himself as the island's first governor. Vicente Yáñez Pinzón had been appointed to take the position of Captain General of the City of Puerto Rico prior to the island's colonization, but he never performed this function. As part of the Spanish Empire, the Spanish monarchy was in charge of appointing the governor of Puerto Rico. The person selected was in charge of the island's development and wealth and was responsible for reporting the colony's status to the government in Spain.

The first native Puerto Rican to perform the function was Juan Ponce de León II, grandson of the conquistador, who served as interim governor in 1579.

After 1580 Puerto Rico's government was established as the Captaincy General of Puerto Rico, and subsequent governors held the office of Captain General as well.

On July 25, 1898, at the outbreak of the Spanish–American War, Puerto Rico was invaded by the United States. Following the conclusion of the war, Spain was forced to cede Puerto Rico, along with Cuba, the Philippines and Guam, to the United States under the 1898 Treaty of Paris. Puerto Rico began the twentieth century under the military rule of the United States with officials, including the governor, who were appointed by the President of the United States.