We investigated the local environment of water confined inside the hollow cylinder of lipid nanotubes (LNTs) by time-resolved fluorescent measurements and attenuated-total-reflectance infrared (ATR-IR) spectroscopy. The LNT was obtained by self-assembly of cardanyl glucosides in water at. room temperature. and had an open-ended cylindrical nanospace with a diameter of 10-15 nm, a length of 10-100 mum, and hydrophilic inner and outer surfaces. We introduced a fluorescent probe of 8-anilinonaphthalene-1-sulfonate into the confined water and observed an extremely slow dynamic Stokes shift, with a correlation time of 1.26 ns, which was 2-3 orders of magnitude longer than that of bulk-phase water. From the peak Shift of the fluorescent spectrum, the local solvent polarity (ET(30)) of the confined water was estimated as 50 kcal/mol, which is 20% lower than that in bulk water. ATR-IR measurements showed that. the hydrogen-bond network of water inside the LNT was more developed than that in bulk water at. room temperature. which is in contrast to the water in other self-assembled confined geometries. such as Aerosol-OT (AOT) reversed micelles.