The invention discloses a self-adaptive key distribution mechanism based on a QKD network, and the mechanism comprises three key strategies: 1, using a classic key independently; 2, independently using a quantum key; and 3, the quantum key and the classic key are used in a fusion manner, so that the condition that the requirement on the key quantity cannot be met due to low quantum key generationrate is avoided. According to the invention, a playing type video is downloaded; Audio information, assigning a candidate packet encryption algorithm for it; AES, 3DES, IDEA, SM1, SMS4, Twofish. The method is used for an RTSP streaming video. Audio information, High real-time performance needs to be guaranteed, The method comprises the following steps: aiming at RTSP streaming video/audio information; assigning a candidate encryption algorithm for it; AES, SM1, SMS4, RC4, Rabbit, ChaCha20, The method has the advantages that the requirements on real-time performance of text information such aselectronic mails and control information are low, a symmetric encryption algorithm is distributed for the application of the type mainly according to the security level required by the application, and accordingly candidate encryption algorithms such as DES, AES, SM1, SMS4 and Twofish can be designated for the application of the type;