Carbon fiber has a wide range of applications in the construction field. For example, some carbon fibers are used in construction projects, such as houses, railways, and tunnels. It can replace steel bars and prestressed steel strands. It can be processed into columns, beams, tubes, and other purposes; it can also directly penetrate into concrete to increase the strength of building materials. This article mainly introduces the application of carbon fiber in construction.At the turn of the 1980s and 1990s, after the Kobe earthquake in Japan and the Los Angeles Earthquake in the United States, scientific and technological engineers found that carbon fiber composite materials could give full play to their advantages in the repair and strengthening of buildings, achieving an unparalleled effect. It has high strength and rigidity, high structural efficiency, the lightest quality, and small weight gain for repair and reinforcement. Using carbon fiber repair, the implementation is also very convenient, easy to operate on-site, the efficiency is higher than the traditional steel reinforcement construction. It also has excellent anti-corrosion properties and strong adaptability to the environment. In those coastal areas, it is vulnerable to salt erosion, and carbon fiber can extend the service life of the building. Besides, its use is very wide, all kinds of buildings, even places of interest can be used to restore it.Using carbon fiber to repair a building can cut costs at 80% of the cost of traditional repairs. The steps are simple and the efficiency is very high. The main operation steps of carbon fiber sheet reinforcement include bottom treatment, removal of the inferior layer, coating of bottom resin, leveling construction surface, sticking carbon fiber sheet and decoration, etc. This technology has great economic benefits. The United States has decided to strengthen all the Bridges to be built on its highways with carbon and good dimensionality. As a major concrete building industry, China is using more and more carbon fiber materials in its buildings.