Cognomen Thanadej (ธนเดช 
, Thanadej 
) , around the world, is an extremely rare surname. Predominantly, Thanadej is the forename as well as the last name.
Tre, Boonsomya, Kaewlumhad, Puangpool, Ramsomphob, Lertkajornsuk, Thumyomajaroen, Throngkitpaisan, Teerapong, Tragulpirom, Tiewsakul, Worasathit, Sathientawat, Phuttanaphong, Ruangrongdidsaya, Dechapattapong, Thammachai, Techataweekit, Wongchalee, Ratchataroj, Theeravarapat, Phichitsakuldej, Yamkayai, Vareekasem, Tiawsakul, Thumyoma, Boon, Suksil, Aumvana, Sukonusa, Attaskulchai, Korkulpath, Kulpitivan, Puntang, Makawong, Sainumpran, Thanasirisin, Simadamrong, Sonsaard, Sooparnich, Chaojirapant, Choothesa, Poungsub, Punthang, Rakphetmanee, Thanetkolchark, Thepmanee, Themanee, Supaprachakorn, and Boonyathananant