A large number of single-crystalline Ag2V4O11 nanobelts with thickness of 10-30 nm, width of 70-200 nm, and lengths of 2-5 mu m have been successfully synthesized by a hydrothermal method. The morphologies and structures of the nanobelts were characterized by x-ray powder diffraction, x-ray photoelectron spectroscopy, transmission electron microscopy, high-resolution transmission electron microscopy, and thermal gravimetric analysis. The magnetic measurement data showed that Ag2V4O11 nanobelts are paramagnetic materials. The nanobelts exhibited an electronic emission turn-on field of 28.9 V mu m(-1), which is the expected macroscopic field 2 required to produce a current density of 10 mu A cm(-2). On the basis of the analytical data, it was observed that Ag2V4O11 nanobelts could serve as a novel candidate for a future field emitter.