Cystoseira crinita can be picked up from the intertidal or shallow sub-tidal hard substrates, which are inhabited by a huge number of associated fauna. One of the most prevalent faunal groups which is associated to those brown algae is the amphipod group. The present work was designed to address the distribution, occurrence and adaptation of amphipods species inhabiting brown algae (Cystoseira crinita Duby, 1830) in relation to the temporal variation. Samples were collected during the warm and cold seasons of 2020, from four replicates sampling points along the northern west Red Sea. A total of 635 individuals of marine amphipods were recorded associated with C. crinita; representing 14 species belonging to 14 genera and 9 families. Faunal distribution is influenced by temporal variation; the recorded species of amphipods were 626 individuals (98.6%) during winter, while during summer, only 9 individuals (1.4%) were detected. Data showed that three amphipod species (Ampithoe ramondi Audouin, 1826, Cymadusa filose Savigny, 1816, and Photis lamellifera Schellenberg, 1928) collectively comprised 78.7 % of the total abundance. The current study highlighted the morphological characterizations of the abundant amphipod species adapting to live in association with C. crinita.