Regardless of whether the ancient Chinese painting is the ink freehand brushwork or is the painting with fine brushworks and detail, it is not painted fully on the paper in the picture, and there are a lot of blank left. We generally call it the blank. In the traditional Chinese painting, the blank is not as the blank paper, it is an important constituent element, and is the part of forming a complete picture. "Blank" can be understood as an element of leaving proper space to give the main object enough space for stretching freely. Therefore, "blank" can't be understood as the "vanity". It is a kind of "hidden imagery" technique, and that's what the ancients said, "the more the scene hidden, the more profound the meaning." Blank has the irreplaceable significance and position in Chinese painting.