This contribution majorly describes the isolation of different collagens from marine Demosponges collected from Gulf of Mannar (GoM), India. Based on the preliminary studies (biochemical and anatomical evaluation of around 40 sponge species collected at GoM), few of the shortlisted sponges were subsequently analyzed for the collagen presence and in particular, Ircinia fusca was focused for further isolation and characterization of different collagens. Chapter I provides background information introducing the subjects presented in the topic of marine sponge biology and its scope. Chapter II narrates the brief methodology of each experiment starting from the collection of marine sponges and up to the immuno-electrophoretic characterization of collagens. Chapter III brought the findings of each experimental procedure that involved the isolation and characterization of different collagens from the experimental sponges. Chapter IV discusses the overall aspects of the different parameters involved in isolation, characterization and purification of marine sponge collagens in the current study as well as the future perspectives of the marine sponges.