A transition piece for a wind turbine tower including a hollow frustoconical piece that is connected to an upper ring and a lower ring. The upper ring is connected to crossbars and the lower ring to radial columns. The transition piece also includes three connectors, each of them being connected to a crossbar, two radial columns and two connection profiles that keep the three connectors joined together, so that a pair of radial columns is arranged between a connector and the lower ring and the crossbars are arranged between the upper ring and a respective connector. The radial columns form an angle of between 65° and 75°, measured between the longitudinal axis of the corresponding radial column with the normal axis of the frustoconical piece.