Casciana Terme Lari is a comune (municipality) in the Province of Pisa in the Italian region Tuscany, located about southwest of Florence and about southeast of Pisa.
Casciana Terme Lari borders the following municipalities: Capannoli, Cascina, Chianni, Crespina Lorenzana, Santa Luce, Ponsacco, Pontedera, Terricciola.
The municipality is composed by twelve frazioni (towns and villages):
The municipality of Casciana Terme Lari was created on 1 January 2014 by merging the former municipalities of Casciana Terme and Lari. The municipal seat is in Lari.