Lousika (Greek: Λουσικά) is a village in Achaea, Greece. It is located 5 km southeast of Kato Achaia, 3 km south of Alissos, and 20 km southwest of Patras. In 2001 Lousika had a population of 604 for the village and 793 for the community, which includes the villages Ypsili Rachi and Spaliaraiika. Lousika was the seat of the former municipality of Olenia. The river Serdini flows through the village.