The 2016 United States Senate election in Illinois was held on November 8, 2016, to elect a member of the United States Senate to represent the State of Illinois, concurrently with the 2016 U.S. presidential election, as well as other elections to the United States Senate in other states and elections to the United States House of Representatives and various state and local elections.

Mark Steven Kirk is an American retired politician and attorney who served as a United States senator from Illinois from 2010 to 2017, and as the United States representative for Illinois's 10th congressional district from 2001 to 2010. A member of the Republican Party, Kirk describes himself as socially liberal and fiscally conservative.