An antenna is provided for a backscatter-based RFID transponder with an integrated receiving circuit, having a capacitive input impedance, for receiving a radio signal lying spectrally within an operating frequency range, whereby the antenna has two antenna arms, which extend outwardly in a spiral from a central area, in which the antenna arms can be connected to the integrated receiving circuit. According to the invention, each antenna arm has an arm length along the arm, which is selected so that one of the series resonance frequencies of the antenna is below the operating frequency range and the next higher parallel resonance frequency of the antenna is above the operating frequency range. The invention relates furthermore to a backscatter-based RFID transponder with an antenna of this type.