Two chalices and other communion supplies were taken from St. Bartholomew's Catholic Church in Elmhurst.
The thieves took the items from a closet inside the church sometime Saturday night after the evening service.
Authorities say the stolen items are worth more than $5,000.
The door to the church was open at the time, and the items were stored in a closet in the back of the church.
Church leaders did not discover the theft until Sunday morning, before services began.
Anyone with information is asked to call Crime Stoppers at 1-800-577-TIPS.
