Vainiūnai (formerly Russian: Войнюны) is a village in Kėdainiai district municipality, in Kaunas County, in central Lithuania. According to the 2011 census, the village had a population of 14 people. It is located 4.5 kilometres (2.8 mi) from Beinaičiai, by the Lankesa river and the Bubliai Reservoir. The road Šėta-Nociūnai goes nearby. There is a water tower and a farm.