Domestic Box Office For May 1991
| Rank | Release | Gross | Max Th | Opening | % of Total | Open Th | Open | Close | Distributor |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Backdraft | $77,868,585 | 1,983 | $12,686,200 | 16.3% | 1,852 | May 24 | - | Universal Pictures |
| 2 | What About Bob? | $63,707,829 | 1,805 | $9,216,334 | 14.5% | 1,463 | May 17 | - | Walt Disney Studios Motion Pictures |
| 3 | Thelma & Louise | $45,360,915 | 1,180 | $6,101,297 | 13.5% | 1,179 | May 24 | - | Metro-Goldwyn-Mayer (MGM) |
| 4 | Soapdish | $36,489,888 | 1,275 | $6,736,380 | 18.5% | 1,275 | May 31 | - | Paramount Pictures |
| 5 | Only the Lonely | $21,830,957 | 1,553 | $5,997,993 | 27.5% | 1,521 | May 24 | - | 20th Century Fox |
| 6 | F/X2 | $21,082,165 | 1,502 | $5,455,058 | 25.9% | 1,499 | May 10 | - | Orion Pictures |
| 7 | Hudson Hawk | $17,218,080 | 2,072 | $7,082,820 | 41.1% | 2,071 | May 24 | - | TriStar Pictures |
| 8 | Switch | $15,545,943 | 1,013 | $3,770,991 | 24.3% | 1,013 | May 10 | - | Warner Bros. |
| 9 | Madonna: Truth or Dare | $15,012,935 | 652 | $543,250 | 3.6% | 51 | May 10 | - | Miramax |
| 10 | Drop Dead Fred | $13,878,334 | 933 | $3,625,648 | 26.1% | 851 | May 24 | - | New Line Cinema |
| 11 | One Good Cop | $11,276,846 | 1,454 | $3,360,277 | 29.8% | 1,353 | May 3 | - | Walt Disney Studios Motion Pictures |
| 12 | A Rage in Harlem | $10,438,504 | 545 | $2,458,080 | 23.5% | 540 | May 3 | - | Miramax |
| 13 | Stone Cold | $9,151,887 | 1,729 | $2,811,154 | 30.7% | 1,729 | May 17 | - | Columbia Pictures |
| 14 | Wild Hearts Can't Be Broken | $7,294,835 | 1,662 | $2,710,416 | 37.2% | 1,662 | May 24 | - | Walt Disney Studios Motion Pictures |
| 15 | Mannequin: On the Move | $3,752,428 | 1,540 | $1,692,817 | 45.1% | 1,540 | May 17 | - | 20th Century Fox |
| 16 | Straight Out of Brooklyn | $2,712,293 | 75 | $58,918 | 2.2% | 5 | May 22 | Oct 17 | The Samuel Goldwyn Company |
| 17 | Everybody's Fine | $1,745,470 | 48 | $18,367 | 1.1% | 1 | May 31 | Oct 3 | Miramax |
| 18 | Citizen Kane 1991 Re-release | $1,585,634 | - | - | - | - | May 1 | - | Paramount Pictures |
| 19 | Truly Madly Deeply | $1,554,742 | 48 | $4,009 | 0.3% | 1 | May 3 | Oct 10 | The Samuel Goldwyn Company |
| 20 | An Angel at My Table | $1,054,638 | 20 | $12,905 | 1.2% | 2 | May 17 | Oct 10 | Fine Line Features |
| 21 | Talkin' Dirty After Dark | $978,775 | - | - | - | - | May 17 | - | New Line Cinema |
| 22 | Dice Rules | $637,327 | - | - | - | - | May 17 | - | Seventh Art Releasing |
| 23 | Auntie Danielle | $604,624 | 17 | $20,730 | 3.4% | 2 | May 17 | Aug 22 | Miramax |
| 24 | Rich Girl | $561,000 | 1,058 | $368,056 | 65.6% | 1,058 | May 3 | - | Studio Three Film Corporation |
| 25 | Sweet Talker | $382,510 | 409 | $258,105 | 67.5% | 409 | May 10 | May 23 | New Line Cinema |
| 26 | The Ballad of the Sad Cafe | $184,890 | 1 | $2,343 | 1.3% | 1 | May 3 | - | Angelika Films |
| 27 | Crooked Hearts | $30,964 | - | - | - | - | May 31 | Sep 26 | Metro-Goldwyn-Mayer (MGM) |
| 28 | Opening Night | $23,488 | 1 | $10,491 | 44.7% | 1 | May 17 | - | Castle Hill Productions |
