Lanaja is a municipality in the province of Huesca, in the Aragon region of northeastern Spain. It lies within the comarca of Monegros, a largely arid and sparsely populated area of the Ebro Depression.
According to the 2011 census (INE), the municipality had a population of 1,381 inhabitants. The village of Lanaja itself accounts for approximately 1,100 of these residents, while the neighbouring villages of Cantalobos and Orillena together comprise an additional 400.
The municipality is therefore made up of a main village surrounded by smaller settlements, a settlement pattern typical of this dry, rural part of Aragon.