The Dutchman, who was last night voted PFA Players' Player of the Year, has been in lethal form this season, plundering 27 Premier League goals.
Van Persie's spectacular form has caught the attention of Manchester City and Juventus, who are said to be keen on the 28-year-old.
Dein, who was vice-chairman when the striker signed in 2004, praised Van Persie's loyalty to the club.
"He is very important to the club and it is not every day you can get a guy who can score over 30 goals in a season," said Dein.
"There was a lot of competition at the time and we are very fortunate he signed for us. I was delighted and he has proved the point because he has been such a prolific goalscorer for the club.
"He has done a great job for the club and the fact that he has stayed with the club all this time, when he has had plenty of opportunities to go elsewhere, says a lot about Robin's character."
Van Persie moved to North London from Dutch side Feyenoord.