| Karabelyov, Yanis | Bulgaria U17 |  Bulgaria | Midfield |
| Karaboue, Loosemy | Nancy (FRA) |  France | Midfield |
| Karachanakov, Anton | Bulgaria U21 | Bulgaria | Midfield |
| Karachun, Valeria | Belarus WU19 |  Belarus | Defender |
| Karačić, Goran | Bosnia and Herzegovina U17 |  Bosnia and Herzegovina | |
| Karadžić, Zorica | Napredak (SRB) / Serbia WOCO |  Serbia | Defender |
| Karadžić, Vladan | Montenegro U19 |  Montenegro | Forward |
| Karageorgiev, Georgi | Varna (BUL) | Bulgaria | Defender |
| Karagounis, Giorgos | Panathinaikos (GRE) / Greece |  Greece | Midfield |
| Karagounis, Thanassis | Atromitos (GRE) / Greece U21 | Greece | Midfield |
| Karagounis, Vassilis | Olympiacos (GRE) / Greece U19 | Greece | Defender |
| Karahmet, Senad | Mechelen (BEL) | Bosnia and Herzegovina | |
| Karakoleva, Nikoleta | Bulgaria WOCO | Bulgaria | Defender |
| Karalis, Ioannis | AEK (GRE) | Greece | Forward |
| Karamanos, Tasos | Atromitos (GRE) / Greece U21 | Greece | Forward |
| Karanfilovski, Ivan | Serbia U19 | Serbia | Defender |
| Karanovic, Goran | Servette (SUI) |  Switzerland | Forward |
| Karapetian, Artem | Armenia U19 |  Armenia | Goalkeeper |
| Karapetsas, Thodoros | Kerkyra (GRE) | Greece | Midfield |
| Karapetyan, Artur | Malatia (ARM) / Armenia FUT | Armenia | Defender |
| Karapetyan, Sargis | Banants (ARM) / Armenia U21 | Armenia | Forward |
| Karapetyan, Anna | Armenia WOCO | Armenia | Goalkeeper |
| Karapetyan, Marine | Armenia WOCO | Armenia | Midfield |
| Karapetyan, Lilit | Armenia WOCO | Armenia | Forward |
| Karapetyan, Gevorg | Banants (ARM) / Armenia U21 | Armenia | Forward |
| Karapetyan, Anna | Armenia WOCO | Armenia | Midfield |
| Karaš, Kamil | Košice (SVK) / Slovakia U21 |  Slovakia | Midfield |
| Karašausks, Artūrs | Latvia U21 |  Latvia | Forward |
| Karasiovaite, Samanta | Gintra (LTU) |  Lithuania | Midfield |
| Kárason, Kolbeinn | Valur (ISL) / Iceland U21 |  Iceland | Forward |
| Karasová, Radka | Slovakia WU17 | Slovakia | Defender |
| Karavayev, Oleksandr | Ukraine U21 |  Ukraine | Midfield |
| Karčemarskas, Žydrūnas | Gaziantepspor (TUR) / Lithuania | Lithuania | Goalkeeper |
| Karchaoui, Sakina | France WU17 | France | Midfield |
| Kärcher, Marcel | Germany U19 |  Germany | Forward |
| Karchouni, Ghoutia | France WU19 | France | Midfield |
| Kardash, Volodymyr | Energy (UKR) | Ukraine | Goalkeeper |
| Kardum, Ivan | Austria Wien (AUT) |  Croatia | Goalkeeper |
| Karelis, Nikos | Amkar (RUS) / Greece U21 | Greece | Forward |
| Karibayeva, Saule | BIIK (KAZ) / Kazakhstan WOCO |  Kazakhstan | Midfield |
| Karikari, Kwame | AIK (SWE) |  Ghana | Forward |
| Karike, Tomas | HJK (FIN) / Finland U21 |  Finland | Goalkeeper |
| Karimova, Turkana | Azerbaijan WU19 |  Azerbaijan | Midfield |
| Karius, Loris | Mainz (GER) | Germany | |
| Karkac, Duygu | Austria WU17 |  Austria | Midfield |
| Karkliņš, Edgars | Daugava Rīga (LVA) / Latvia U21 | Latvia | Midfield |
| Kārkliņš, Krišs | Latvia U17 | Latvia | Midfield |
| Karl, Lisa | Germany WU17 | Germany | Defender |
| Karlen , Gaëtan | Sion (SUI) | Switzerland | Forward |
| Karlen, Gregory | Sion (SUI) | Switzerland | Midfield |
