Current watermarking algorithms use mostly pseudo random sequences to generate watermarks. These algorithms emphasize the improvement of imperceptibility and robustness of the watermarking but ignores its safety. To improve the watermarking safety， a new secure communication oriented airspace watermarking algorithm with a tamper locating function was proposed based on the true randomness of quantum key. According to the principle of BB84 protocol， the quantum key with real randomness and absolute security generated by quantum key distribution mechanism was used to generate binary image watermarks. Then， in combining with a quantum key matrix model and 8-neighborhood random location idea， the quantum watermarks were embed into a carrier image dynamically and randomly. At the end of the transmission， the receiver could quickly extract watermark information， accurately judge the integrity of the watermark image and the security of the transmission process， and could perform tamper localization. The concealment， robustness and tamper location of the algorithm were tested. The experimental results show that the algorithm is simple， safe， and has higher safety and covert and its tamper locating accuracy is 3 pixel×3 pixel. The algorithm can be widely used in the secure transmission of digital images.