Kalula Distant, 1901, Genus – synonym of Durmia Stål, 1865, Genus
Kangra Kirkaldy, 1902d, Genus – synonym of Creontiades Distant, 1883, Genus
Karamania Kormilev, 1938, Genus – synonym of Artheneis Spinola, 1837, Genus
Karenocoris Miller, 1954, Genus
Karocris V.G. Putshkov, 1975, Genus
Kaschmirocoris Lindberg, 1939, Genus
Kasumiphylus Schwartz & Stonedahl, 2004, Genus
Keliocoris Ren, 1992, Genus – synonym of Oncocephalus Klug, 1830, Genus
Keriahana Distant, 1918, Genus – synonym of Neostrachia Saunders, 1877, Genus
Kerzhneriola Josifov, 1979, Genus – synonym of Atomoscelis Reuter, 1875, Genus
Khondana Distant, 1918, Genus – synonym of Anchesmus Stål, 1876, Genus
Kiangsia Yang, 1934, Genus – synonym of Paterculus Distant, 1902, Genus
Kilicanata Seidenstücker, 1956a, Genus – synonym of Dasyscytus Fieber, 1864, Genus
Kirkaldyia Montandon, 1909, Genus
Kitocoris Herring, 1967, Genus
Kitoko Schouteden, 1923, Genus – synonym of Ammianus Distant, 1903, Genus
Kleidocerini J.A. Slater, 1952, Subfamilia – synonym of Ischnorhynchinae Stål, 1872, Subfamilia
Kleidocerus: Burmeister, 1835, Genus – misspelled name of Kleidocerys Stephens, 1829, Genus
Kleidocerys Stephens, 1829, Genus
Kleydocerus: Signoret, 1885, Genus – misspelled name of Kleidocerys Stephens, 1829, Genus
Klinophilos Kirkaldy, 1899, Genus – synonym of Cimex Linnaeus, 1758, Genus
Kohnometopus Yasunaga, 2005, Genus
Kokeshia Miyamoto, 1960, Genus
Korasiocapsus Kirkaldy, 1902d, Genus – synonym of Stenotus Jakovlev, 1877, Genus
Koreocoris Cho & Kwon, 2008, Genus
Kotovelia Matsumura, 1913, Genus – synonym of Rhagovelia Mayr, 1865, Genus
Ktenofer Roubal, 1965b, Genus – synonym of Megalonotus Fieber, 1860, Genus
Kulichoderes Štys, 2002, Genus
Kundakimuka Cassis, 1995, Genus
Kuschakewitschia Oshanin,1891, Genus – nomen nudum of Cercinthinus Kiritshenko, 1916, Genus