The invention discloses a method for building a house by cutting mountain rock. A house body is of a frame structure. A frame column is formed in the mode that rock is cut after downward punch filling pile construction is carried out on the rock. A frame beam horizontally connected with the frame column is formed by pouring concrete on transverse embedded steel bars. According to the method for building the house by cutting mountain rock, a traditional building method that excavation is carried out at first, and then a house body structure is constructed upwards is broken through, and the inverse method that the house body structure is constructed at first, and then excavation is carried out is adopted. The mountain rock is cut after a punch filling pile is driven in the rock body to form the house frame structure, and the pile length and diameter can be freely changed based on design requirements; a pile end can enter a supporting layer or embedded into a rock layer, the structure is higher in strength and high in stability, the cut-out rock can be directly used as a building decoration material, the structural features of the rock are sufficiently utilized, the unique style that the house is built around a mountain is formed, local materials are used, stone materials are sufficiently utilized, the economic cost is reduced, and the house with the high structural strength and shock resistance is built.