The crash happened at about 13:00 on Friday 23 October at kilometre 101.300 of Ruta 1, near Boca del Cufré in San José department, the traffic police said.
The motorhome was travelling east to west on Ruta 1 with four people on board: three men and one woman, all adults. It collided front-to-side with a lorry that was coming along the Boca del Cufré road and tried to join Ruta 1 from south to north.
The woman passenger died. Two other people were injured. The motorhome driver was not injured in the initial assessment, and the lorry driver was unhurt. The causes of the crash are under investigation. The road was fully reopened, and police said they would release further details on the ages and diagnoses of the injured.