The annual pilgrimage celebrates the Catholic icon who is said to have made her first appearance on December 12, 1531.
Worshippers believe she appeared to a native Indian in Mexico City, an Aztec Indian, and asked him to build a church for her. Since then, she has been visited by millions.
The first gathering in Des Plaines was held 25 years ago and happens every year.
"She is part of history and an important part of my life," said Marina Galindo.
"Our blessed Mother brings us closer to God. This event brings families together and tells us how important it is," said Father Marco Mercado, Archdiocese of Chicago.
Music, Aztec dancing and serenades were part of the festivities, and followers placed candles and roses on the shrine.
"I try to follow the customs so my kids can grow up adoring her," said one worshipper.
Mass was held on Wednesday morning in tribute.