The invention discloses a secret optical communication system based on dynamic strong dispersion management, belonging to the technical field of secret communication, and comprising an optical signal emission part, an optical signal encryption part, an optical signal transmission part, an optical signal receiving part and an optical signal decryption part; the optical signal encryption part is provided with a fixed and adjustable dispersion module; the optical signal decryption part is provided with a fixed and adjustable dispersion compensation module; the dispersion module and the dispersion compensation module are formed by any one of a fiber bragg grating, a G-T etalon, an MEMS (Micro-Electromechanical System), a PLC (Programmable Logic Controller) annular resonant cavity; one end of the optical signal encryption part is connected to an optical signal transmitter, and the other end of the optical signal encryption part is connected to the optical signal transmission part; secret keys are transmitted to the optical signal decryption part through key secrete channels; one end of the optical signal decryption part is connected to the optical signal transmission part, and the other end of the optical signal decryption part is connected to an optical signal receiver; and the optical signal decryption part carries out real-time, synchronous and precise compensation on the transmitted optical pulse according to information provided by the secrete keys for releasing signals. In the secret communication, a dynamic dispersion management technology is used in the optical communication system for the first time to realize the secret transmission of information.