Abstract: To investigate the failure modes and load-bearing performance of pre-tightened tooth connections of carbon fiber reinforced polymer (CFRP) in the bridge engineering, a total of 68 tensile specimens were carried out with transverse pre-tightened force (23 MPa, 34.6 MPa, 53 MPa, 64.5 MPa), tooth depth (0.5 mm, 1 mm, 2 mm), tooth length (8 mm, 16 mm, 24 mm) and tooth number (one tooth, three teeth and six teeth) as variable parameters. According to the test results of load displacement curve, strain and failure mode, the effects of various parameters on the mechanical properties of the joint were analyzed. The results show that there are four failure modes for CFRP pre-tightened tooth joints: Shear failure, crushing failure, longitudinal splitting failure and fiber breaking failure. There are two characteristics of the load-displacement curves of the joint: The load drops suddenly after reaching the extreme value and the load decreases slowly after reaching the extreme value. The former joints are subjected to shear failure or fiber breaking failure, while the latter joint is subjected to crushing failure or splitting failure. The load distribution ratio of pre-tightened multi-tooth joints is uneven, the load distribution ratio of the joint with crushing failure is more uniform than that of joint with shear failure. Whether the joint is crushing or shear failure, the load distribution ratio of the first tooth is the largest. The more the number of joint teeth, the smaller the maximum load distribution ratio of the joint. When the pre-tightened force, tooth depth and tooth length are less than 53 MPa, 2 mm and 16 mm respectively, the joint strength increases with the increase of pre-tightened force, tooth depth and tooth length. When the pre-tightened force and tooth length exceed a certain value of 53 MPa and 16mm respectively, the joint connection strength changes little. In the range of 6 teeth, the joint strength increases with the increase of the number of teeth.