The invasive Hemidactylus mabouia (Moreau de Jonnès, 1818) is one of the most widespread introduced species of reptiles, being present in the New World at least 500 years ago. In this work, we report for the first time, the presence of the invasive gecko H. mabouia in the dry Chaco, a biogeographic region included in the Gran Chaco Sudamericano. We collected 3 individuals in an urban zone at Las Lomitas, Patiño department, Formosa Province, Argentina. This new record extends the distribution range of this introduced species by nearly 300 km (in a straight line) from Formosa city, the nearest point previously reported.