Abstract: According to the certifiable security of quantum key distribution protocol and pseudo random characteristics of the chaotic sequence, a new image encryption method that combined quantum key and chaotic mapping was proposed. Firstly, initial quantum key was obtained with BB84 protocol, then quantum key was formed after error checking for the initial key with data consulting approach, and the last key stream was achieved by combining the quantum key and chaotic sequence from Logistic mapping. Lastly, pixel values were replaced with XOR operation of pixel values and the last key stream, and image was encrypted. Simulation results and analysis show that, the new cryptographic algorithm can more effectively resist statistics-based and plain text attack, while ensuring the security of key transformation; the key stream results from the new method is highly sensitive to initial parameters.