Lentiai is a comune (municipality) in the province of Belluno in the Italian region of Veneto, located about 70 kilometres (43 mi) northwest of Venice and about 20 kilometres (12 mi) southwest of Belluno. As of 31 December 2004, it had a population of 3,020 and an area of 37.6 square kilometres (14.5 sq mi).

Lentiai borders the following municipalities: Cesiomaggiore, Feltre, Mel, Santa Giustina, Valdobbiadene, Vas.