EVEN WITH THE DISENTURNMENT OF THIS GREAT MAN WE WILL NEVER KNOW IF THE MONA lisa was a self portrait. The best evidence is the similiarity of the nose......but his nose is much larger then Lisa's ---and if it were a self portrait the two would match better than they do.

"Giuseppe Pallanti, author of a recent study of Lisa Gherardini, wife of the Florentine silk merchant Francesco del Giocondo and the original Mona Lisa, says Leonardo probably met her in the church of Santissima Annunziata, where the del Giocondo family had a chapel.

Leonardo left Santissima Annunziata in 1502 to serve as military architect and engineer to Cesare Borgia, the notorious son of Pope Alexander VI. But he returned to Florence after ten months to paint the Mona Lisa, among other masterpieces, and stayed until 1506, when he returned to Milan.

The discovery was announced at a press conference coinciding with the opening of a Leonardo exhibition at the Palazzo Panciatichi in Florence and another on the Atlantic Codex and Leonardo’s inventions at the Palazzo Corsini in Rome."

Source:
The Times January 12, 2005

"Found: the studio where Leonardo met Mona Lisa"
From Richard Owen in Rome

http://www.timesonline.co.uk/tol/news/world/article411195.ece