# Swimming at the 2018 Summer Youth Olympics – Boys' 100 metre breaststroke

The boys' 100 metre breaststroke event at the 2018 Summer Youth Olympics took place on 7 and 8 October at the Natatorium in Buenos Aires, Argentina.

## Results
### Heats

The heats were started on 7 October at 11:00.
| Rank | Heat | Lane | Name | Nationality | Time | Notes |
| 1 | 3 | 5 | Michael Houlie | South Africa | 1:01.37 | Q |
| 2 | 4 | 4 | Sun Jiajun | China | 1:01.43 | Q |
| 3 | 3 | 4 | Taku Taniguchi | Japan | 1:01.68 | Q |
| 4 | 2 | 5 | Yu Hanaguruma | Japan | 1:02.22 | Q |
| 5 | 2 | 4 | Vladislav Gerasimenko | Russia | 1:02.46 | Q |
| 6 | 4 | 3 | Jan Kałusowski | Poland | 1:02.63 | Q |
| 7 | 3 | 3 | Caspar Corbeau | Netherlands | 1:02.74 | Q |
| 8 | 4 | 5 | Denis Petrashov | Kyrgyzstan | 1:02.82 | Q |
| 9 | 2 | 7 | Phạm Thanh Bảo | Vietnam | 1:02.99 | Q |
| 10 | 2 | 3 | Vitor de Souza | Brazil | 1:03.18 | Q |
| 11 | 4 | 7 | Sebestyén Böhm | Hungary | 1:03.21 | Q |
| 12 | 4 | 6 | Juri Dijkstra | Netherlands | 1:03.53 | Q |
| 13 | 4 | 8 | Santiago Saint-Upery | Uruguay | 1:03.55 | Q |
| 14 | 3 | 7 | Demirkan Demir | Turkey | 1:03.68 | Q |
| 15 | 3 | 1 | Moncef Aymen Balamane | Algeria | 1:03.72 | Q |
| 16 | 3 | 2 | André Klippenberg Grindheim | Norway | 1:03.80 | Q |
| 17 | 3 | 6 | Alexander Milanovich | Canada | 1:03.88 | |
| 18 | 4 | 1 | Jānis Vitauts Siliņš | Latvia | 1:04.06 | |
| 19 | 3 | 8 | Maximillian Ang | Singapore | 1:04.24 | |
| 20 | 1 | 4 | Aleksey Sidorchuk | Uzbekistan | 1:04.31 | |
| 21 | 2 | 8 | Marcus Mok | Hong Kong | 1:04.46 | |
| 22 | 4 | 2 | Andrés Puente | Mexico | 1:04.69 | |
| 23 | 2 | 2 | Ethan Dang | United States | 1:04.72 | |
| 24 | 1 | 2 | Dávid Gajdoš | Slovakia | 1:04.87 | |
| 25 | 2 | 1 | Didzis Rudavs | Latvia | 1:04.95 | |
| 26 | 1 | 3 | Matija Može | Slovenia | 1:04.96 | |
| 27 | 2 | 6 | Izaak Bastian | Bahamas | 1:05.21 | |
| 28 | 1 | 6 | Luis Weekes | Barbados | 1:06.27 | |
| 29 | 1 | 5 | David Solis | Costa Rica | 1:06.32 | |
| 30 | 1 | 8 | Samuele Rossi | Seychelles | 1:07.28 | |
| 31 | 1 | 1 | Leonard Kalate | Papua New Guinea | 1:07.53 | |
| 32 | 1 | 7 | Simon Greuter | Liechtenstein | 1:08.12 | |

### Semifinals

The semifinals were started on 7 October at 18:38.
| Rank | Heat | Lane | Name | Nationality | Time | Notes |
| 1 | 2 | 4 | Michael Houlie | South Africa | 1:00.23 | Q |
| 2 | 1 | 4 | Sun Jiajun | China | 1:00.61 | Q |
| 3 | 1 | 6 | Denis Petrashov | Kyrgyzstan | 1:01.95 | Q |
| 4 | 1 | 5 | Yu Hanaguruma | Japan | 1:01.99 | Q |
| 5 | 2 | 5 | Taku Taniguchi | Japan | 1:02.08 | Q |
| 6 | 2 | 3 | Vladislav Gerasimenko | Russia | 1:02.15 | Q |
| 7 | 1 | 3 | Jan Kałusowski | Poland | 1:02.23 | Q |
| 8 | 2 | 6 | Caspar Corbeau | Netherlands | 1:02.29 | Q |
| 9 | 2 | 2 | Phạm Thanh Bảo | Vietnam | 1:02.52 | |
| 10 | 1 | 2 | Vitor de Souza | Brazil | 1:02.69 | |
| 11 | 1 | 7 | Juri Dijkstra | Netherlands | 1:03.10 | |
| 12 | 2 | 7 | Sebestyén Böhm | Hungary | 1:03.23 | |
| 13 | 2 | 8 | Moncef Aymen Balamane | Algeria | 1:03.35 | |
| 14 | 1 | 8 | André Klippenberg Grindheim | Norway | 1:03.65 | |
| 15 | 2 | 1 | Santiago Saint-Upery | Uruguay | 1:03.84 | |
| 16 | 1 | 1 | Demirkan Demir | Turkey | 1:04.05 | |

### Final

The final was held on 8 October at 19:02.
| Rank | Lane | Name | Nationality | Time |
| | 5 | Sun Jiajun | China | 1:00.59 |
| | 3 | Denis Petrashov | Kyrgyzstan | 1:01.34 |
| | 2 | Taku Taniguchi | Japan | 1:01.40 |
| 4 | 6 | Yu Hanaguruma | Japan | 1:01.62 |
| 5 | 4 | Michael Houlie | South Africa | 1:01.70 |
| 6 | 8 | Caspar Corbeau | Netherlands | 1:01.81 |
| 7 | 7 | Vladislav Gerasimenko | Russia | 1:02.43 |
| 8 | 1 | Jan Kałusowski | Poland | 1:02.69 |