Abstract: In the current information hiding algorithms, most of the secret images are binary images or gray-scale images, and the extracted secret images are not lossless. A lossless information hiding algorithm for color QR codes with large coding capacity is proposed. Firstly, the carrier image is decomposed into three channels, then each channel is divided into blocks separately. The low-frequency components of the block areas are obtained by DCT transformation. Color QR code is scrambled by Arnold, and then encrypted by Logistic mapping, the three channels of encrypted color QR code are hidden in the low-frequency components of corresponding channel blocks of color carrier image. The rounding errors caused by data type transformation in the process of DCT hiding algorithm is hidden, which are used for data compensation in the process of secret image extraction. The experimental results show that the algorithm can effectively complete the hidden and lossless extraction of color QR code and common color secret image, and has good invisibility and security.