In order to ensure the security of communication data transmission in high efficiency spectral hybrid modulation MMwave fiber network communication, a method of secure data transmission in mmwave fiber network communication under double clustering algorithm is proposed. A hybrid modulation millimeter-wave optical fiber network communication channel model is constructed, and the dual functions of dimming control and efficient spectrum data transmission are combined to control the optical fiber network communication channel balance. An electromagnetic coupling modulation method is adopted to establish the multipath interference suppression model of the optical fiber network communication channel, the carrier modulation signal is introduced to adjust the output stability of the optical fiber network communication data, and the light intensity disturbance parameter is introduced to realize the efficient spectrum hybrid modulation and demodulation of millimeter-wave optical fiber network communication. The high-frequency feature quantity of optical fiber network communication security data is extracted, and the dual clustering algorithm is used to realize the block clustering processing of optical fiber network communication data, and the cascade channel path gain estimation of millimeter wave optical fiber network communication is realized. According to the parameter estimation result, the secure transmission of data is realized by combining channel modulation and anti-jamming design. The simulation results show that the bit error rate is 10^-12, the signal-to-noise ratio is 49dB, the antiinterference ability is strong, and the transmission security and timeliness are good.