Abstract—The development of science and technology is undergoing speedy growth. And the construction should be also changed in the current digital transformation. Concrete 3D printing is a new technology in the construction industry. It contributes to modernization based on new and cut-edge characteristics. This new technology saves considerable labor as well as costs. Thus, the material used in concrete 3D printing plays an important role. Because concrete is a mixture of many components that meets the requirements of the concrete 3D building structure. Recycled PET resin and coir fibers are mixed into concrete to replace other aggregates in this study. The use of recycled and natural waste from various commodities in concrete 3D printing is an appealing and safe disposal strategy. The idea of using recycled PET resin and natural fibers as raw materials for concrete comes from the problem of environmental pollution. This method can reuse waste from PET resin and other resins with similar properties to it. That can solve the majority of the environmental issues created by recycled materials. In addition, using natural fibers is also a current trend to protect the environment. The material tests and experiments on concrete 3D printing buildings have been evaluated and showed good results.