The Vimanmek Mansion is a former royal palace in Bangkok, Thailand. It is also known as Vimanmek Palace. It is located in the Dusit Palace complex, nearby Dusit Zoo in Dusit district.

In 1897 King Rama V paid a royal visit to Europe visiting many of the Royal Palaces. Upon his return he purchased orchards and paddy fields between Padung Krungkasem Canal and Samsen Canal for the construction of a royal garden which he named “the Dusit Garden” - see Dusit Palace for more on the palace area.

Vimanmek Palace was constructed in 1900 by having the Munthatu Rattanaroj Residence in Chuthathuj Rachathan at Ko Sichang, Chonburi, dismantled and reassembled in Dusit Garden as the first permanent residence in the garden. Nails were used during in its construction. The interior decoration combines Europe’s neoclassical style with traditional Thai motifs and architecture and early 20th Century modernisation.

The celebration for the completion of the 72 room Vimanmek Palace was held on 27 March 1901. It was used as a royal palace by King Rama V for five years until the completion of Amphorn Satharn Villa in 1906. In 1932, Vimanmek Palace was used only as a storage place of the Bureau of the Royal Household.

In 1982 Queen Sirikit asked permission of King Rama IX to renovate Vimanmek Palace for use as a museum to commemorate King Rama V by displaying his photographs, personal art and handicrafts, and to serve as a showcase of the Thai national heritage. The palace is now a major tourist attraction and is the world's largest golden teakwood mansion. Many of the gifts and treasures that King Chulalongkorn collected on his European trip are now displayed in the museum.