ISP said troopers responded to the crash on southbound I-294 near Devon Avenue just before 4:30 a.m. The maintenance workers were fixing potholes there when a driver struck them.
All three workers were taken to local hospitals, where one of them died, ISP said.
The medical examiner later identified the man killed as 52-year-old Calvin L. Holley, of Chicago.
State police later arrested 37-year-old Paul R. Ong of Berwyn, ISP officials said Wednesday.
Ong has been charged with one count of Aggravated Driving Under the Influence Involving Death, officials said.
The suspect is being held in custody pending his first court appearance.
Illinois Gov. JB Pritzker issued a statement over the weekend, saying, "Heartbreaking news this morning as three tollway workers were struck in Des Plaines while working.
May their memory be a blessing, and may we come together to pray for the injured.
Remember to slow down and keep our workers safe."
Illinois Tollway Executive Director Cassaundra Rouse also issued a statement, saying, "The Illinois Tollway Board and all Tollway staff are devastated by the loss of one of our Illinois Tollway roadway maintenance workers.
This equipment operator/laborer has worked with the Illinois Tollway for the past two years and was a respected and valued member of the Tollway.
Our equipment operator/laborers work on the front line of our 294-mile roadway system, performing duties that included maintaining safe roadway conditions and assisting drivers who were stranded or needed help. He was carrying out these duties when he tragically lost his life on the Tri-State Tollway (I-294).
Roadway workers, police officers and everyday motorists are too often hurt, injured or worse because drivers are not following the Move Over Law. The Tollway reminds everyone to slow down and change lanes safely when approaching any vehicle with flashing lights on the road.
We offer our deepest condolences and our full support to family, loved ones and friends for this heartbreaking loss."
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