Gold single-crystal nanobelts were synthesized by a nitric-acid-induced seed-mediated growth method. The morphologies and structures of the products were characterized by TEM and HRTEM; the absorption property was analyzed by UV-vis spectrum. TEM observation shows that nanobelts are dominant morphology with perfect fcc single-crystal structure and there are some nanoplates and nanoparticles. The UV-vis spectra reveal a strong longitudinal surface plasma resonance (SPR) band and a weak transverse SPR band centered at ~975 nm and ~550 nm, respectively. The growth mechanism of the nanobelts is the self-assembly of the adjacent nanoplates through surface dipole-dipole interaction with nitric acid induction