Ashmyanka (Belarusian: Ашмянка [ʌʂˈmʲankə], Lithuanian: Ašmena, Polish: Oszmianka, Russian: Ошмянка) is a river in Belarus. Tributary of Neris (Wilia), it has a length of 104 km, starting from the village of Muravanaya Ashmyanka and passing through the town of Ashmyany (Oszmiana). It is located in the north of Hrodna Voblast.