Disclosed are a signal processing device and an image display apparatus including the same. The signal processing device and the image display apparatus including the same according to an embodiment of the present disclosure includes: a first decoder to reconstruct image data received from an external electronic device, an encoder to compress the image data reconstructed in the first decoder, a memory to store the image data compressed in the encoder, and a second decoder to reconstruct the image data stored in the memory. Accordingly, despite of the increases of the amount of the input image data and the bandwidth thereof, the image data may be stored in the memory efficiently.