Drilled and tapped high-strength steel plates are possible replacements of nuts and can be combined with high-strength bolts to form new assemblies that are used as blind bolts for steel tube column frame joints. In order to study the tensile capacity and failure mechanism of steel plate composite bolts, on the basis of our experimental research results, 64 specimens were tested under monotonic tensile load by ABAQUS software. The thicknesses of four types of steel plates (i.e., Q345B, 45#, Q460C, and Q690D) and the diameters of five specifications of high-strength bolts (i.e., M16, M20, M24, M27, and M30) in grade 10.9 were investigated. Results show that the Q345B, Q460C, and Q690D steel plates can replace the 45# steel plate. The tensile value of the steel plate composite bolts can be designed as 70% of the ultimate tensile load of the screw thread under reliable anchored. For thin steel plates, the bolt was pulled out, the steel plate thread experienced shear failure, the out-of-plane deformation of the steel plate was larger than 1/200 of the support distance, and the screw maximum stress located in the anchoring area. For thick steel plates, the bolt experienced tensile fracture, and the screw maximum stress located in the structural area. The positions of the maximum stress of the steel plates in the two failure modes were both at the first thread. In order to avoid the steel plate thread failure in the steel plate composite bolt, it is suggested that the thicknesses of Q345B, Q460C, and Q690D steel plates should be no less than 1.15d, 1.10d, and 0.95d, respectively. Based on the elastic mechanics and thread-related research, the formula for tensile capacity of high-strength steel plate composite bolts was derived. The calculated results were in good agreement with the finite element results. The research results can provide a reference for the design of high-strength steel plate composite bolts.