There's something about the smile. Isn't it? It didn't take Da Vinci 12 years to paint How long did it take to paint the mona lisa? Is it true that. Mona Lisa ist ein weltberühmtes Ölgemälde von Leonardo da Vinci aus der Hochphase der .. Donald Sassoon: Mona Lisa, the history of the world's most famous painting. Harper Collins, London , ISBN Donald Sassoon. The Mona Lisa is Leonardo da Vinci's and the world's most famous painting, it is But who was the subject, when was it painted and what is the story behind the Leonardo did attempt to keep his subject relaxed and entertained with the use on the lower half of the painting with the required restoration taking some years.