Players ATPWTA
| Name | Country |
|---|---|
| Tim Kopinski | USA |
| Vit Kopriva | CZE |
| Sebastian Korda | USA |
| Warut Korkiatthaworn | THA |
| Evgeny Korolev | KAZ |
| Vladimir Korolev | RUS |
| Mikhail Korovin | RUS |
| Stanislav Korshunov | RUS |
| Daniel Kosakowski | USA |
| Ivan Kosec | SVK |
| Mika Kosonen | FIN |
| Bernd Kossler | AUT |
| Oleg Kossov | RUS |
| Viktor Kostin | GER |
| Pavel Kotov | RUS |
| Aleksandar Kovacevic | USA |
| Yuriy Kovalenko | ISR |
| Egor Kovalev | RUS |
| Jozef Kovalik | SVK |
| Dmytro Kovalyov | UKR |
| Mateusz Kowalczyk | POL |
| Keita Koyama | JPN |
| Victor Kozin | RUS |
| Nikita Kozlov | RUS |
| Stefan Kozlov | USA |
| Vitaly Kozyukov | RUS |
| Sahr Timothy Kpulun | SLE |
| Pavel Krainik | CAN |
| Austin Krajicek | USA |
| Filip Krajinovic | SRB |
| Filip Kraljevic | CRO |
| Vladyslav Kramarov | UKR |
| Konstantin Kravchuk | RUS |
| Maxim Kravtsov | RUS |
| Kevin Krawietz | GER |
| Gero Kretschmer | GER |
| Ivan Krivic | CRO |
| Neven Krivokuca | CRO |
| Milan Krnjetin | SRB |
| Ondrej Krstev | CZE |
| Pedja Krstin | SRB |
| Mitchell Krueger | USA |
| Vladimir Kruk | BLR |
| Kyryll Kryvchun | CAN |
| Nikita Kryvonos | USA |
| Yuriy Kryvoy | UKR |
| Andre Ku Meza | PER |
| Jason Kubler | AUS |
| Lukasz Kubot | POL |
| Denis Kudla | USA |