A video encoding apparatus may include a partitioning unit which divides a frame included in input video into a plurality of blocks and a rate control module which adjusts a first quantization parameter value of a block corresponding to a region of interest among the plurality of blocks based on a first CBF (current buffer fullness) value of the region of interest, and adjusts a second quantization parameter value of a block corresponding to a non-region of interest among the plurality of blocks based on a second CBF value of the non-region of interest.