Here are the Russian Orthodox saints that start with the letter "K," with their feastdays where applicable:
- Kalliope, June 8
- Katharine the Martyr
- Kenelm, King of Mercia, July 17
- Ketevan of Georgia, September 22
- Kira and Marina
- Kola, Nine Martyred Children of
- Ksenia
- Kuksha of the Kiev Caves, August 27
- Kyra, February 28
- Kyranna of Thessalonia, February 28
- Kyria, Virgin Martyr of Palestine, June 6
Source: http://www.gnisios.narod.ru/lives.html