The world’s largest reservoir containing extensive biodiversity, deep sea, is far from well known. Owing to intricacy in gaining access to these distinct ecosystems, deep-sea technology is an essential technique to explore and effectively monitor life in extreme conditions. A myriad of deep-sea sampling strategies is available depending on the type of species. The physical parameters of the benthic environment determine the structure, form, and function of sea-bottom ecosystems. To clarify the function of deep-sea equipment as a promoter of life advancement in ecosystem studies, this chapter highlights the state-of-the-art deep-sea equipment suited for investigating extreme ecosystems. Therefore, the equipment associated with exploring the deep-sea ecosystems are introduced and analyzed comprehensively. The direct sampling techniques, in situ observations, and remote sensing techniques are being discussed. This chapter culminates with the procedure of sample preservation, sorting, and examination.