Water is essential for the stability and function of biological macromolecules. In living systems, essential water-related phenomena occur in restricted geometry in cells, and at active sites of proteins and membranes or at their surface. In this paper, we present the more recent results on the structure of confined water as compared with that of bulk supercooled water. In particular, the combined effects of the hydration level and the temperature on the change of the structure of water are discussed in the light of powerful techniques.