This paper aims to study cave paintings from an aesthetic point of view. Even though cave paintings are human artworks, researches only have been conducted from the religious, archaeological, and ecological perspectives. Therefore, it is worth studying the aesthetics of cave paintings as works of art. The main features of cave paintings are the fact that the exhibition hall is a cave rather than a white cube, and that the human iconographies are combined with other living things. Compared to general exhibition halls and iconographies of humans, those of cave paintings are unique. The inside of the cave is dark and humid, and the surface of the walls is uneven. Human figures drawn on the cave walls are combined with animals, plants, or unknown creatures. As these variations of cave interiors and human iconographies are difficult to define, predict, or imagine, viewers are puzzled and frightened. The most suitable aesthetic concept for the art work of cave paintings with these characteristics is the grotesque. The word grotesque comes from the Italian word 'grotta', meaning cave, and was first used in a 15th-century painting found in the basement of a Roman palace. According to Wolfgang Kaiser's study on the use of the word 'grotesque' in German and French, the key symbol of the grotesque is the figure of a monstrous creature, a chaotic mixture of animals, foliage, and humans in distorted proportions. Thus, the grotesque can be defined as the collapse and unfamiliar change of the world, which was familiar to us and operated according to a fixed order, is engulfed in confusion. The cave gives viewers a sense of unfamiliarity through its features of low illumination and uneven walls, which are different from general exhibition spaces. The human figure in the cave paintings is a combination of animals, plants, and something unknown to the human body that the viewer encounters daily, giving the viewer confusion. The implications of this thesis are to study cave paintings from an aesthetic point of view. And the cave paintings are grotesque works of art that cause eerie and bewildering emotions in the viewer. Also, although the concept of grotesque was formed in the 15th century, there are some artworks made before the 15th century, such as cave paintings, to which the grotesque is applied. Therefore, this study argues that it is necessary to expand the scope of research on grotesque.