In order to explore the photoelectric applications of CuS materials, copper sulfide (Cu2-xS) nanotubes were prepared via hydrothermal method. The structure and morphology of the Cu2-xS were characterized with X-ray diffraction (XRD) and scanning electron microscopy (SEM). The surface optoelectronic properties of the products and their photovoltaic properties in varying electric field were investigated by UV-vis spectrophotometer, surface photovoltage spectrum (SPS), and field-induced surface photovoltage spectroscopy (FISPS). The results show that the outer diameter, thickness, and length of the nanotubes are 325—675 nm, 70—125 nm, and 10—20 μm, respectively. There are two absorption areas in the wavelength range of 300—800 nm according to the UV-vis spectrum. The FISPS shows that the copper sulfide (Cu2-xS) nanotubes are n-type semiconductor.