Map - Hormigueros, Puerto Rico (Hormigueros Municipio)

Hormigueros is a town and municipality of Puerto Rico located in the western region of the island, northeast of Cabo Rojo; northwest of San Germán; and south of Mayagüez. Hormigueros is spread over 5 barrios and Hormigueros Pueblo (the downtown area and the administrative center). It is part of the Mayagüez Metropolitan Statistical Area.

The region of what is now Hormigueros belonged to the Guaynia region, located on the southwest portion of Puerto Rico. Archaeological findings have established that there were tribes already settled in the region around 820 BC.

During the Spanish colonization at the beginning of the 16th century, European colonizers settled in the area. A coffin found underground the basilica was tested in laboratories and was dated prior to 1600. Historians also mention the Horomico River as one of the main sources of gold during the rush of the era. In 1692, the settlement that would become the town of Hormigueros was first established as a village of San Germán. It was founded by Giraldo González de la Renta (sometimes spelled Geraldo).

After its initial establishment, Hormigueros belonged to the municipality of San Germán. From 1863 to 1873, residents of Hormigueros made formal petitions to be separated from San Germán and be declared an independent municipality. They were finally granted their independence as a municipality on April 1, 1874, being its first mayor Narciso Oller Serra.

Puerto Rico was ceded by Spain in the aftermath of the Spanish–American War under the terms of the Treaty of Paris of 1898 and became a territory of the United States. In 1899, the United States Department of War conducted a census of Puerto Rico finding that the population of Hormigueros was 3,215.

After the American invasion of 1898, Hormigueros was annexed this time to the town of Mayagüez. The annexation was ordered by Guy V. Henry, but according to Adolfo de Hostos, it was a town's petition. In 1912, they were granted their independence once again, although there were attempts to annex them again during 1928–29.

On September 20, 2017 Hurricane Maria struck Puerto Rico. In minute Hormigueros, 651 residences were affected. The hurricane triggered landslides in Hormigueros with its wind and rainfall.