The celebration is scheduled from 2 to 3 p.m. on the downtown green at Post and Reef roads, the First Selectman's office announced.
New England champion Fairfield American was eliminated from the series Tuesday night in a loss to the West champion, Petaluma Calif. The team was due to arrive back in Fairfield this afternoon.
At Thursday's rally, First Selectman Mike Tetreau will officially welcome the team home, his office said. Players and coaches also will address supporters and talk about their success and experiences in Williamsport.
The 12- and 13-year-old players have been away from home for nearly three weeks, living first at a Little League complex in Bristol during the New England Regional Championship and for the last 10 days at the World Series complex in Williamsport.
Fairfield American bowed out of the double-ellimination World Series with a 2-2 record.
But the team streaked to its district and sectional championships in southern Connecticut, then beat Avon for its third consecutive state championship. American finished with an overall 21-3 record.
The the trip to the World Series -- the deam of millions of Littile Leaguers around the globe -- was Fairfield American's second in three years. American's 2010 News England championship team won one game and lost two in Williamsport. Last year's team fell one win short of getting to Williamsport.