The CFRP-confined concrete filled circular steel tube (C-CFST) stub columns are under initial loading state in service stage. The mechanical properties of CFRP reinforced CFST stub columns under initial loading and the effect of reinforcement are of great concern to engineering field. The yield bearing capacity of C-CFST stub columns strengthened with CFRP under initial loading state is analysed through theoretically and simulated in this research. The theoretical equation of the yield strength of C-CFST axial compression stub columns strengthened with CFRP under initial load is proposed. The finite element model (FEM) process of C-CFST stub columns under initial loading strengthened by CFRP is described. Theoretical results are compared with the FEM results to verify the correctness of the theoretical equation and the rationality of the FEM. The verified equation and model are afterwards used to predict the yield strength of C-CFST stub columns strengthened with CFRP under initial load, which provides a reference method for calculating the yield strength of CCFST stub columns strengthened with CFRP under initial loading.