Granjeno is a city in Hidalgo County, Texas, United States. The population was 293 at the 2010 census. The city sits on the banks of the Rio Grande, near the border with Mexico. Its name comes from the granjeno tree (Celtis pallida) or spiny hackberry.
Founded in the late 18th century, Granjeno has a history that predates Texas statehood. Granjeno Cemetery was established in 1872 with burials from both sides of the Rio Grande. By the mid-1930s, the community consisted of several dwellings. A church and school were established in Granjeno by 1948. During the 1960s, growth in the community was stimulated by the development of a colonia.
Granjeno is located at 26°8′18″N 98°18′13″W (26.138316, -98.303484). It is situated off the junction of FM 494 and Old Military Road in southern Hidalgo County, approximately four miles southwest of McAllen.
Granjeno is part of the McAllen–Edinburg–Mission and Reynosa–McAllen metropolitan areas.