The mechanical properties of CFRP without epoxy resin were tested by the monotonic load method, and the corresponding stress-strain relationship curve was established. The probability model and the parameter fitting based on Weibull distribution theory were applied, and the characteristic strength parameter and the shape parameter of CFRP were obtained. Three large scale RC short columns were constructed, the specimen not retrofitted, specimen strengthen retrofitted by CFRP and specimen repaired by CFRP which has been damaged by earthquake were simulated respectively. Quasi-static testing was carried out. The hysteretic-loop curve and average framework curve were obtained, furthermore, the performance of ductility and strength were analyzed and compared. The calculational results approximately agree with the experimental results, which prove the validity of OpenSees. The short columns retrofitted by CFRP have superior ductility so as to enhance the seismic performances effectively. The residual seismic behavior of short columns can also meet the requirement of seismic code. The research provides reference to seismic analysis and engineering design of retrofitted reinforcement concrete structures.