Two new sympatric isopod species of the genus Castellanethes (Olibrinidae) are described from caves located in the Western High Atlas of Morocco. Both species present troglomorphic traits, such as the absence of body pigmentation and eyes and are, therefore, considered cave-dwelling species (troglobitic). Castellenethes ougougensissp. nov. was found in five caves, while C. ighousisp. nov. is an amphibious species found in only two caves, which also harbour populations of C. ougougensissp. nov. Additionally, notes on their habitats are provided, as well as a discussion on their conservation status.