The Mesa River (Spanish: Río Mesa) is a river in the Sierra de Solorio range area, Iberian System, Spain.

There are trout in the river, but the population of the endangered European freshwater crayfish in the river has practically disappeared owing to the introduction of the North American signal crayfish (Pacifastacus leniusculus).

[1] It rises near Selas, in the province of Guadalajara, Castile-La Mancha.

The Mesa has an irregular flow, due to the long dry season of the summer months, with often heavy rainfall in the spring and autumn.

It receives much water at Jaraba, where there are thermal springs.