His autographed jersey from Stage 7 is for sale on eBay until June 20. The bidding reached $6,600 on Monday.
Proceeds will go to Ryders Cycling Society of Canada, a non-profit founded by Hesjedal last year "to create and sustain opportunities for Canadians to ride bicycles."
The Victoria native became the first Canadian to win one of the three "Grand Tour" events, which includes the Tour de France and the Vuelta a Espana, on May 27.
Hesjedal confirmed last week he will be Garmin-Barracuda's team leader for the Tour de France starting June 30.
A pink jersey goes to the overall leader at the end of each of the Giro's stages. Hesjedal first earned it on Stage 7 and held it for two more before reclaiming it on Stage 14.
"Auctioning my first pink jersey to support cycling in Canada," Hesjedal tweeted Monday. "Bid and take home part of cycling history."