The present invention relates to a OFDM signal receiver device that performs weighting for branch metrics based on average noise power or signal-to-noise power ratio and conducts Viterbi decoding based on the result of the weighting. In the present invention, based on a demodulated signal, electric power corresponding to a noise component contained in the demodulated signal is calculated. A noise power signal corresponding to the result of the calculation is output from a noise power-calculating unit 8. Based on the noise power signal and a transmission channel characteristic corresponding to a subcarrier component that is output from an interpolation filter unit, a weighing factor for a branch metric is calculated by a weighting factor-calculating unit 9, and based on the weighting factor, the demodulated signal is decoded by decoding unit 10.