Aiming at the problem of communication eavesdropping, based on the research project of "research on self-secured optical communications theories and technologies", the existing technology development of fiber physical layer security transmission is introduced at the information level, carrier level and modulated signal level. This paper proposes a fiber physical layer secure transmission technology based on quantum noise stream cipher. The orthogonal frequency division multiplexing based on DFT-spread(DFTs-OFDM) is introduced into the quantum noise stream cipher transmission system based on quadrature amplitude modulation(QAM), which can effectively resist the eavesdropping of non-partners while ensuring high spectrum utilization. The research results show that the optical transmission rate of 10 Gb/s has no relay transmission distance of 300 km, and the Q factor exceeds 9, and the information interception probability is less than 0.001%.