List of Famous people born in Illinois, United States of America

Dennis DeYoung is an American singer-songwriter, musician and producer. He is a founding member of the rock band Styx as primary lead vocalist and keyboardist, a tenure that lasted from 1970 until June 1999. DeYoung has been credited as the writer of more Styx songs than any other Styx member. He was also the band's most successful writer, penning 7 of the band's 8 Billboard top 10 singles as well as a solo top 10 single.

Muhal Richard Abrams was an American educator, administrator, composer, arranger, clarinetist, cellist, and jazz pianist in the free jazz medium. He recorded and toured the United States, Canada and Europe with his orchestra, sextet, quartet, duo and as a solo pianist. His musical affiliations constitute a "who's who" of the jazz world, including Max Roach, Dexter Gordon, Eddie "Lockjaw" Davis, Art Farmer, Sonny Stitt, Anthony Braxton, and The Art Ensemble of Chicago.

Álvaro Montoya is an American professional ice hockey goaltender who is currently an unrestricted free agent. He most recently played for the Bakersfield Condors in the American Hockey League (AHL) while under contract to the Edmonton Oilers of the National Hockey League (NHL). He was drafted by the New York Rangers in the first round, sixth overall, in the 2004 NHL Entry Draft after a three-year career with the University of Michigan. Montoya is the first Cuban-American to play in the NHL. Montoya was born in Chicago, Illinois, but grew up in nearby Glenview, Illinois.

Donald Glen Wilson, nicknamed "The Dragon", is an American martial artist and actor. An 11-time professional kickboxing world champion who scored 47 knockouts in four decades, he has been called by the STAR System Ratings as "perhaps the greatest kickboxer in American history. He has disposed of more quality competition than anyone we've ever ranked". He is an entrant into the European Martial Arts Hall of Fame.

Emil Ferris is an American writer, cartoonist, and designer. Ferris debuted in publishing with her 2017 graphic novel My Favorite Thing Is Monsters. The novel tells a coming-of-age story of Karen Reyes, a girl growing in 1960s Chicago, and is written and drawn in the form of the character's notebook. The graphic novel was praised as a "masterpiece" and one of the best comics by a new author.

James Tobin was an American economist who served on the Council of Economic Advisers and consulted with the Board of Governors of the Federal Reserve System, and taught at Harvard and Yale Universities. He developed the ideas of Keynesian economics, and advocated government intervention to stabilize output and avoid recessions. His academic work included pioneering contributions to the study of investment, monetary and fiscal policy and financial markets. He also proposed an econometric model for censored dependent variables, the well-known Tobit model.

Kevin Dunn is an American actor who has appeared in supporting roles in a number of films and television series since the 1980s.

Oscar "Budd" Boetticher Jr. was an American film director. He is most famous for a series of low-budget Westerns he made in the late 1950s starring Randolph Scott.

Mary-Claire King is an American geneticist. She was the first to show that breast cancer can be inherited due to mutations in the gene she called BRCA1. She studies human genetics and is particularly interested in genetic heterogeneity and complex traits. She studies the interaction of genetics and environmental influences and their effects on human conditions such as breast and ovarian cancer, inherited deafness, schizophrenia, HIV, systemic lupus erythematosus and rheumatoid arthritis. She has been the American Cancer Society Professor of the Department of Genome Sciences and of Medical Genetics in the Department of Medicine at the University of Washington since 1995.

Christine Ko is a Taiwanese-American actress, known for her role as Emma on the CBS sitcom The Great Indoors. Before her success in America, she had a brief career in Taiwan in the early 2010s.