Players ATPWTA
| Name | Country |
|---|---|
| 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 |
| Alexander Kudryavtsev | RUS |
| Nicola Kuhn | GER |
| Mikhail Kukushkin | KAZ |
| Shusaku Kumakura | JPN |
| Andrey Kumantsov | RUS |
| Sameer Kumar | USA |
| Jan Kuncik | CZE |
| Igor Kunitsyn | RUS |
| Souma Kuribayashi | JPN |
| Alexandr Kushakov | UKR |
| Gary Kushnirovich | USA |
| Sanetulla Kutibaev | UZB |
| Dimitar Kutrovsky | BUL |
| Dimitar Kuzmanov | BUL |
| Alex Kuznetsov | USA |
| Andrey Kuznetsov | RUS |
| Mykhailo Kvantaliani | UKR |
| Thai-Son Kwiatkowski | USA |
| Oh-Hee Kwon | KOR |
| Soon Woo Kwon | KOR |
| Kevin Kylar | CAN |
| Patrick Kypson | USA |
| Sergis Kyratzis | CYP |
| Nick Kyrgios | AUS |
| Henri Laaksonen | SUI |
| Eduardo Lacalle | CHI |
| Felipe Lacalle | CHI |
| Lukas Lacko | SVK |
| Alexandre Lacroix | FRA |
| Tommaso Lago | ITA |