Incumbent Republican governor James R. Thompson won a third term in office, defeating the Democratic nominee, former United States Senator Adlai Stevenson III, by a slim margin of 5,074 votes.

Grace Mary Stern won the Democratic primary for lieutenant governor unopposed.

George Ryan defeated Susan Catania and Donald L. Totten in the lieutenant gubernatorial primary.

Stevenson complained that Thompson was trying to portray him as an ineffectual elitist by famously stating, "He is saying 'Me tough guy,' as if to imply that I'm some kind of wimp.

"[4] Before the election, Thompson had been favored by polls and predictions to win by roughly twenty percentage points.

[5] The nominees of the third-party Libertarian and Taxpayers tickets were both right-of-center, and were therefore regarded as more likely to siphon off more potential supporters from Thompson than from Stevenson.

However, despite the Republican ticket performing weaker in downstate Illinois than it had in the 1978 election, the Republican ticket still managed to win downstate Illinois by a 136,917 vote margin, which was a key factor in securing their victory.

[3][1][8] 183,311 of the 3,856,875 individuals that cast ballots in the state's 1982 general election did not vote in the gubernatorial race.

[6] On December 7, 1982 Stevenson and Stern filed a petition with the Illinois Supreme Court requesting a recount.

[9] Stevenson and Stern's petition argued that the election had been impacted by "widespread irregularities and error".

[10] Stevenson claimed that the partial recount in the precincts he had selected had found enough invalid ballots to decrease Thompson's margin-of-victory from 5,074 to merely 325 votes.

Thompson argued that many of the ballots which Stevenson had characterized as illegitimate had been so-characterized due to "defacing" that was actually the result of markings from electronic tabulating machines.

[10] On January 7, 1983, the court issued a 4–3 decision, with a majority opinion authored by Chief Justice Howard C. Ryan, rejecting Stevenson's petition for a recount.

[9][6] The majority opinion of the court found insufficient evidence of either mistakes, fraud, or irregularities to warrant a recount.

[10][6] The opinion cited the 1975 state decision Rice v. Cunningham in finding that, "the General Assembly did not have the authority to provide that a case be heard by a three judge panel," and that, "the 1970 Constitution confers no authority in the legislature to create new courts".

[14] Authorities alleged that they had discovered large fraud involving vote buying and voter impersonation.

Authorities alleged that in one instance, they discovered that a ballot which had been cast for the Democratic Party slate was tabulated 198 times.

Some Democrats have alleged that fraud might have committed by Republicans in areas outside Chicago to secure Thompson his victory.

[15][18] In 2016, Rudy Giuliani suggested that the gubernatorial results had been fraudulent on the part of Chicago Democrats.