Semiana is a comune in the Province of Pavia in the Lombardy region in Italy. It is about 50 km southwest of Milan and about 35 km west of Pavia. As of 31 December 2004, 256 people lived there. It has an area of 9.9 km².[3]
Semiana is next to these municipalities: Lomello, Mede, Sartirana Lomellina, Valle Lomellina, Velezzo Lomellina.