Veisiejai is a city in the Lazdijai district municipality, Lithuania. It is located 18 km (11 mi) south-east of Lazdijai. There is a church dedicated to St. George (built in 1817), an old estate with a park, high school, kindergarten "Ąžuoliukas", a post office (postal code LT-67043), a museum and monuments dedicated to the composer J. Neimontas and L. L. Zamenhof.
Veisiejai is one of few towns that are located in a lake peninsula. The western part of the town is surrounded by a park from the 18th century. There are several lakes in the vicinity of the town. The biggest of them – Ančia – divides the town into two parts. Lake Snaigynas is in the east, Lake Vernijis in the north, and Lake Veisiejis in the southwest. The town is named after the lake Veisiejis which is situated 6 km south-west of Veisiejai.