Guayanilla is a town and municipality of Puerto Rico located on the southern coast of the island, bordering the Caribbean Sea, south of A…Guayanilla is a town and municipality of Puerto Rico located on the southern coast of the island, bordering the Caribbean Sea, south of Adjuntas, east of Yauco; and west of Peñuelas and about 12 miles west of Ponce. Guayanilla is spread over 16 barrios and Guayanilla Pueblo. It is part of the Yauco Metropolitan Statistical Area.