| Election Name: | 2010 Illinois Senate election |
| Country: | Illinois |
| Type: | legislative |
| Ongoing: | no |
| Previous Election: | 2008 Illinois Senate election |
| Previous Year: | 2008 |
| Next Election: | Illinois Senate elections, 2012 |
| Next Year: | 2012 |
| Seats For Election: | 21 of 59 total seats in the Illinois State Senate |
| Majority Seats: | 30 |
| Image1: | John Cullerton (cropped).jpg |
| Leader1: | John Cullerton |
| Party1: | Democratic Party (United States) |
| Leaders Seat1: | 6th-Chicago |
| Last Election1: | 37 |
| Seats1: | 35 |
| Seat Change1: | 2 |
| Popular Vote1: | 634,294 |
| Percentage1: | 54.22% |
| Swing1: | 0.25% |
| Leader2: | Christine Radogno |
| Party2: | Republican Party (United States) |
| Leaders Seat2: | 41st-La Grange |
| Last Election2: | 22 |
| Seats2: | 24 |
| Seat Change2: | 2 |
| Popular Vote2: | 530,130 |
| Percentage2: | 45.15% |
| Swing2: | 0.38% |
| Map Size: | 350px |
| President | |
| Posttitle: | President-Elect |
| Before Election: | John Cullerton |
| Before Party: | Democratic Party (United States) |
| After Election: | John Cullerton |
| After Party: | Democratic Party (United States) |
The 2010 elections for the Illinois Senate was conducted on Tuesday, November 2, 2010. The 2010 primary election was conducted on Tuesday, February 2, 2010. State Senators elected this year sat for two year terms, all of which expired at the beginning of the next General Assembly.
| Illinois State Senate Elections, 2008 | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Party | Votes | Percentage | Seats up | Seats not up | Total before | Total after | +/– | ||
| Democratic | 634,294 | 54.47% | 14 | 23 | 37 | 35 | align="right" | -2 | |
| Republican | 530,130 | 45.53% | 7 | 15 | 22 | 24 | +2 | ||
| Totals | 1,164,424 | 100.00% | 21 | 38 | 59 | 59 | — | ||