The municipality of Tlahuelilpan is one of the eighty-four municipalities that make up the state of Hidalgo, in Mexico. Its municipal head is the locality of Tlahuelilpan. The municipality is located to the south west of the Hidalgo territory between the parallels 20°06 'and 20°10' north latitude. The meridians 99°09 'and 99°15' west longitude. With an altitude between 2100 and 2200 meters above sea level, this municipality has an area of 28.18 km2, and represents 0.14% of the surface area of the state, within the geographical region known as Valle del Mezquital. It borders to the north with the municipalities of Tezontepec de Aldama and Mixquiahuala de Juárez. To the east with the municipality of Tetepango.
To the south with the municipalities of Tetepango and Tlaxcoapan. To the west with the municipalities of Tlaxcoapan and Tezontepec de Aldama. Tlahuelilpan is considered within the metropolitan municipalities of the metropolitan area of Tula, also integrated by the municipalities of Tula de Allende, Atitalaquia, Atotonilco de Tula and Tlaxcoapan, being Tula de Allende the central municipality.