The risque portrait, which shows his third wife completely naked, is on display at the Castle Fine Art gallery in London, where the rocker is exhibiting his Raw Instinct collection.
The canvas, simply titled 'Sally', is the most expensive piece in the display, with a price tag of $320,000. Other works, centring around his music career, range in price from $16,000 (£10,000) to $80,000 (£50,000).
Humphreys posed for Wood in his studio at the gallery, and the guitarist says, "We always have fun together, Sall's (sic) great at modelling. There's plenty more, we did some more recently in the Seychelles."