Rosario de Lerma is a town in the center of the province of Salta, Argentina. It is the administrative seat of the Rosario de Lerma Department, located in the Lerma Valley, roughly 30 kilometers south of the provincial capital, also named Salta.
The town sits in an agricultural valley of northwestern Argentina, an area known for tobacco cultivation and other crops. It lies along the route connecting Salta with the Calchaquí Valleys to the south, and is served by the narrow-gauge railway line that historically linked the region.
Rosario de Lerma functions as a local service and commercial center for the surrounding rural area. Its position in the Lerma Valley places it within the broader Andean foothill region of Salta Province.