Burg Vondern, Medieval castle in Oberhausen, Germany.

Burg Vondern is a two-part brick castle in Oberhausen-Vondern: a 17th-century baroque main house with a hipped roof and a late Gothic two-winged outer bailey. The outer bailey's gatehouse has a round-arch frieze, and its round corner towers, called Abortturm and Gerichtsturm, have conical roofs and pointed-arch friezes. A cobbled path leads through the pointed-arch gateway, above which are two windows with blue-and-white diamond-patterned shutters.

The lords of Vonderen, a Cleves ministerial family, are documented from 1162; the castle itself appears in 1266 as the seat of Gerhard de Vondere. In 1401 Dietrich von Vondern divided the estate between his daughters Vredune and Bate, and a castle is first mentioned then. Around 1520 Wessel van Loë rebuilt the outer bailey; the baroque main house followed in the 17th century. The city of Oberhausen acquired the complex in 1946 or 1947 and restored it with the Förderkreis from 1982 to 1995.

The name Vondern comes from the Middle High German "vonder", a narrow footbridge over a watercourse. Every two years the grounds host a medieval market and knight festivals; since 2016 an annual hi-fi fair has also taken place in the castle. The upper floor of the manor house holds the wedding room used by the city of Oberhausen.

The castle is owned by the city of Oberhausen and cared for by the Förderkreis Burg Vondern e.V. The main house holds exhibitions and concerts, and the upper-floor Trausaal is used for civil weddings. A small museum in the Vorburg displays finds from archaeological digs around the castle, and the Remise can be rented for events and seminars.

In 1925, the town of Osterfeld issued a series of emergency banknotes titled "Die Sage vom Schloss Vondern" (The Legend of Vondern Castle), which reproduced the castle on its paper money. The building also houses a small museum displaying objects found in archaeological digs around the site.