JPEG2000 is an ideal satellite image compression scheme. However, most computation is redundant and memory resources are large in JPEG2000, which is difficult to adapt to the transmission of the high real-time requirements and the limited resource satellite images. Therefore, a novel rate control algorithm based on the rate distortion slope of satellite images is proposed. According to the downward trend roughly of the number of bit planes required for the code block and the three properties of the rate-distortion slope, a simple formula is provided to achieve the rate-distortion slope as the threshold of tile 1 encoding, and the code passes that less than this threshold are skipped, so it does not need to code all code passes. Experimental result indicates that the storage of the algorithm accounts for PCRD about 33%, while PSNR remains unchanged at the bit rate of 0.125 bpp. Therefore, this method can effectively improve the coding efficiency of satellite images.