Swimming at the 1991 Pan American Games – Men's 4 × 100 metre medley relay
# Swimming at the 1991 Pan American Games – Men's 4 × 100 metre medley relay

The men's 4 × 100 metre medley relay competition of the swimming events at the 1991 Pan American Games took place on 18 August. The last Pan American Games champion was the United States.

## Results

All times are in minutes and seconds.

| KEY: | q | Fastest non-qualifiers | Q | Qualified | GR | Games record | NR | National record | PB | Personal best | SB | Seasonal best |
| - | - | - | - | - | - | - | - | - | - | - | - | - |

### Final

The final was held on August 18.

| Rank | Name | Nationality | Time |
| - | - | - | - |
| | Andrew Gill Hans Dersch Mike Merrell Joel Thomas | United States | 3:42.84 |
| | - - - - | Puerto Rico | 3:45.78 |
| | - - - - | Cuba | 3:45.96 |
| 4 | - - - - | Canada | 3:48.37 |
| 5 | - - - - | Argentina | 3:54.10 |
| 6 | - - - - | Mexico | 3:54.34 |
| 7 | - - - - | Uruguay | 3:55.95 |
| 8 | - - - - | Trinidad and Tobago | 4:03.61 |
