A system and method for automatic bone extraction from a medical image is provided. A method for automatically extracting a bone from a medical image, comprises: performing a thresholding on the image in an intensity range of the bone to generate a first bit mask; eroding the first bit mask to remove connections between blood vessels and the bone to generate a second bit mask; performing a region growing on the second bit mask starting from a seed point within the intensity range to separate the bone from unconnected blood vessels and to generate a third bit mask; dilating the third bit mask to generate a fourth bit mask; and performing a region growing on the fourth bit mask starting from the seed point within the intensity range to generate a fifth bit mask representing the bone.