The award honours the best stills camera launched onto the Japanese market between 1 April 2011, and 31 March 2012.
The D800 also scooped the Readers Awards title, voted for via an online poll.
Organised by Japan’s Camera Journal Press Club, the awards give the country’s photography magazines the chance to vote on their favourite kit.
‘Equipped with a 36.3-million-pixel image sensor, the Nikon D800 is capable of superior resolution,’ said the judging panel, in a statement released by Nikon.
‘The number and variety of its advanced functions enable recording of both photos and movies with better image quality than ever before.
‘The D800 offers performance and functions equal to those of Nikon’s flagship model, at an affordable price.
‘The extremely durable body also supports use, even under the most severe photographic and environmental situations.’
The awards have been running since 1984.