Vileišis Palace is a Neo-baroque style architectural ensemble in Vilnius, Lithuania, built for Petras Vileišis. Vileišis was a prominent Lithuanian engineer, political activist, publisher, and philanthropist who commissioned the palace in 1904 and supervised its construction. The ensemble consists of a main house, a guesthouse, and an outbuilding. It currently houses the Institute of Lithuanian Literature and Folklore. It was renovated during the early 2000s.