This research aims to contribute to the knowledge of Trichoptera in northwestern Algeria. The study focuses on the identification and classification of various species, including Rhyacophila undetermined, Setodes argentipunctellus McLachlan 1877, Tinodes waeneri, Agapetus undetermined, Oxyethira unidentata McLachlan 1884, and Psychomyia pusilla Fabricius 1781. The research also explores the distribution and habitats of these species, providing valuable insights into their ecology and conservation. The study is based on material examined from various wadis in northwestern Algeria, including Chouly wadi Beni Ghazli, Chouly wadi Yebder, and wadi Safsaf El Ourit. The findings of this research will contribute to the understanding of the Trichoptera fauna in the region and inform conservation efforts.