Volume rendering has been a key technology in the visualization of data sets from various disciplines. However, fast volume rendering of large-scale data sets is still a challenging field due to the vast memory, bandwidth and computational requirements. Two consecutive image slices of volume data usually have very high comparability. It is designed an accelerating footprint volume-rendering method based on comparability of consecutive image slices. When the contribution of the sampling point to screen pixels color value is computed, only the changed contribution of the next slice sampling point changed data value to screen pixels color value is computed. The influencing screen pixels color value is modified based on the changed contribution value. The experiment expresses that the new footprint volume-rendering method can obviously accelerate speed of volume rendering.