A compound with a non-layered structure composed of Cu2-xSe nanotubes was prepared in a room temperature redox reaction in ethylene diamine solution. The product was characterized by x-ray diffractometry, transmission electron microscopy, high resolution transmission electron microscopy, and x-ray photoelectron spectroscopy. Analysis shows that the nanotubes have a multiwall structure with (002) planes of face-centred cubic Cu2-xSe and open ends. The Cu2-xSe nanotubes have length 500 nm, with an inner diameter of 20 nm and an outer diameter of 30 nm on average. Ethylene diamine's ability to achieve strong coordination and the presence of the reducing agent hydrazine hydrate aid the formation of Cu2-xSe nanotubes with mixed valence.