# 1999 Pan Pacific Swimming Championships – Women's 100 metre butterfly

The women's 100 metre butterfly competition at the 1999 Pan Pacific Swimming Championships took place on August 22–23 at the Sydney International Aquatic Centre. The last champion was Jenny Thompson of US.
This race consisted of two lengths of the pool, all in butterfly.

## Records

Prior to this competition, the existing world and Pan Pacific records were as follows:
| World record | Mary T. Meagher (USA) | 57.93 | Brown Deer, United States | August 16, 1981 |
| Pan Pacific Championships record | Jenny Thompson (USA) | 59.00 | Fukuoka, Japan | August 12, 1997 |

## Results

All times are in minutes and seconds.
| KEY: | q | Fastest non-qualifiers | Q | Qualified | CR | Championships record | NR | National record | PB | Personal best | SB | Seasonal best |

### Heats

The first round was held on August 22.
| Rank | Name | Nationality | Time | Notes |
| 1 | Jenny Thompson | United States | 59.26 | Q |
| 2 | Susie O'Neill | Australia | 59.43 | Q |
| 3 | Misty Hyman | United States | 59.89 | Q |
| 4 | Ayari Aoyama | Japan | 1:00.35 | Q |
| 5 | Ashley Tappin | United States | 1:00.76 | Q |
| 6 | Maki Mita | Japan | 1:00.84 | Q |
| 7 | Richelle DePold-Fox | United States | 1:00.85 | Q |
| 8 | Tomoko Hagiwara | Japan | 1:01.04 | Q |
| 9 | Karine Chevrier | Canada | 1:01.13 | Q |
| 10 | Junko Onishi | Japan | 1:01.34 | Q |
| 11 | Jessica Deglau | Canada | 1:01.47 | Q |
| 12 | Jennifer Button | Canada | 1:01.83 | Q |
| 13 | Molly Freedman | United States | 1:01.85 | Q |
| 14 | Renate du Plessis | South Africa | 1:02.05 | Q |
| 15 | Pang Ran | China | 1:02.20 | Q |
| 16 | Andrea Schwartz | Canada | 1:02.26 | Q |
| 17 | Amanda Loots | South Africa | 1:02.55 | |
| 18 | Kate Godfrey | Australia | 1:02.59 | |
| 19 | Sarah Evanetz | Canada | 1:02.66 | |
| 20 | Kelly Stefanyshyn | Canada | 1:02.84 | |
| 21 | Angela Kennedy | Australia | 1:02.87 | |
| 22 | Megan McMahon | Australia | 1:03.00 | |
| 23 | Cho Hee-Yeon | South Korea | 1:03.09 | |
| 24 | Kirsten van Heerden | South Africa | 1:03.91 | |
| 25 | Candice Crafford | South Africa | 1:04.64 | |
| 26 | Candice Nethercott | South Africa | 1:04.74 | |
| 27 | Kuan Chia-hsien | Chinese Taipei | 1:07.29 | |
| 28 | Sung Yi-chieh | Chinese Taipei | 1:07.31 | |

### Semifinals

The semifinals were held on August 22.
| Rank | Name | Nationality | Time | Notes |
| 1 | Jenny Thompson | United States | 58.57 | Q, CR |
| 2 | Susie O'Neill | Australia | 59.44 | Q |
| 3 | Ayari Aoyama | Japan | 1:00.13 | Q |
| 4 | Misty Hyman | United States | 1:00.16 | Q |
| 5 | Richelle DePold-Fox | United States | 1:00.17 | Q |
| 6 | Jessica Deglau | Canada | 1:00.48 | Q |
| 7 | Tomoko Hagiwara | Japan | 1:00.51 | Q |
| 8 | Maki Mita | Japan | 1:00.54 | Q |
| 9 | Ashley Tappin | United States | 1:00.65 | |
| 10 | Karine Chevrier | Canada | 1:00.91 | |
| 11 | Junko Onishi | Japan | 1:01.22 | |
| 12 | Jennifer Button | Canada | 1:01.44 | |
| 13 | Amanda Loots | South Africa | 1:01.71 | |
| 14 | Renate du Plessis | South Africa | 1:01.89 | |
| 15 | Pang Ran | China | 1:01.92 | |
| 16 | Andrea Schwartz | Canada | 1:02.59 | |

### Final

The final was held on August 23.
| Rank | Lane | Nationality | Time | Notes |
| | Jenny Thompson | United States | 57.88 | WR |
| | Susie O'Neill | Australia | 59.07 | |
| | Ayari Aoyama | Japan | 59.58 | |
| 4 | Misty Hyman | United States | 1:00.39 | |
| 5 | Tomoko Hagiwara | Japan | 1:00.63 | |
| 6 | Jessica Deglau | Canada | 1:00.72 | |
| 7 | Amanda Loots | South Africa | 1:01.54 | |
| 8 | Karine Chevrier | Canada | 1:01.57 | |