Tlahualilo de Zaragoza is a city located in the northeastern part of the Mexican state of Durango. Tlahualilo of Zaragoza is the municipal seat of the Tlahualilo municipio. As of 2010, the city had a population of 9,517. The city is part of the Comarca Lagunera metropolitan area, which has a population totalling more than 912,000 inhabitants in 2005.