A flame-retardant seamless belt is formed by molding a thermoplastic composition containing a polyester thermoplastic elastomer as a main component thereof; at not less than 15 wt % nor more than 40 wt % of melamine cyanurate for a whole weight of the thermoplastic composition; and not less than 0.01 parts by weight nor more than three parts by weight of an anion-containing salt, shown by a chemical formula 1, for 100 parts by weight of an entire polymer component. The thermoplastic composition has a volume resistivity of not less than 1.0.times.10.sup.6.OMEGA.cm nor more than 1.0.times.10.sup.12.OMEGA.cm. The flame-retardant seamless belt is used as an intermediate transfer belt (33) or the like for use in an image-forming apparatus such as a copying apparatus, a facsimile, a printer, and the like.