Vedder made the song available on Pearl Jam's Web site this week. It's been buzzing on radios in Chicago and in bars near Wrigley Field.
The lyrics pay homage to a team that hasn't won a World Series for 100 years. The Cubs defeated the St. Louis Cardinals on Saturday to clinch the NL Central title.
"Someday we'll go all the way," the refrain goes. "Yeah, someday we'll go all the way."
Though Vedder became synonymous with the Seattle grunge sound in the '90s, he was born in the Chicago area and is a longtime Cubs fan.
"When you're born in Chicago you're blessed and you're healed the first time you walk into Wrigley Field," Vedder writes.
Vedder's Grammy-winning band is known for such songs as "Alive" and "Evenflow."