Embodiments of the present invention provide a printing system and a printing method for determining an ink-saving amount. The printing system comprises: a rasterizer processor configured to load a content file, and perform a raster process according to a predetermined ink-saving parameter so as to output a raster image; a computer-to-plate (CTP) device configured to output an imaging CTP plate according to the raster image; and a CTP output device configured to print a one-bit Tiff image according to the imaging CTP plate; and an ink-saving amount determination device coupled, in parallel with the CTP device, to the rasterizer processor and configured to acquire a raster image when the ink-saving parameter is disabled and compares the raster image with a raster image acquired from the rasterizer processor when the ink-saving parameter is enabled, so as to determine the ink-saving amount available for the content file.