Adherent and uniform nanostructured mesoporous films of selenium have been produced by electrodeposition from the hexagonal liquid-crystalline phase of a nonionic surfactant. The regular nanostructure consists of 25-Å diameter cylindrical pores distributed on a long-ranged hexagonal lattice. Electron diffraction reveals that selenium is single crystalline with an hcp structure. Current−voltage curves recorded by STM indicate that the electrodeposits are intrinsic semiconductors with an apparent band gap of ≈1.0 eV.