In the process of data decryption, the real-time voice encrypted communication based on waveform symbol mapping method is subject to bit errors and data loss. To address this problem, this paper proposes a synchronous decryption scheme for real-time voice encrypted communication based on frame ID. On the basis of the frame-by-frame encryption and decryption of voice data, a voice frame format with good error correction capability and satisfying the coding length is designed according to the error characteristics of waveform symbol mapping method, and the frame ID and frame pattern are obtained and confirmed by the voice frame determination algorithm for simultaneous decryption. The experimental results show that, compared with other schemes, the scheme in this paper can reduce the bit error rate (BER) of the voice signal after waveform demodulation, but does not reduce the transmission rate.