To cope with increasingly serious problems related to image security, this study proposes a digital image hiding algorithm based on two-dimensional (2D) Logistic mapping and 2D discrete cosine transform (2D-DCT). Firstly, the chaotic sequence generated by the 2D Logistic mapping is used to diffuse and scramble pixels of the secret image so that the secret image can be encrypted. Then, 2D-DCT is performed on the host image in blocks, and the image information after diffusion and scrambling is stored in the lower right corner of each block after 2D-DCT. Finally, 2D inverse discrete cosine transform (2D-IDCT) is carried out to yield the stego image. Experimental results also show that the proposed algorithm is safe, feasible, and effective in image hiding.