In this study, two reinforced concrete frames with hollow clay tile masonry infill walls, retrofitted with diagonally applied carbon fiber-reinforced polymer (CFRP), which were tested previously, were analytically investigated. A simple material model for the masonry infill wall strengthened with CFRP is suggested. The lateral strength of each rehabilitated frame was obtained by pushover analysis of four different models using a commercially available finite-element program, and the results were compared with the test results. We also determined the lateral strength of the CFRP-applied masonry infill walls, and compared the results with the results obtained from existing analytical models. Drift capacity of the masonry infill walls strengthened with CFRP was also investigated, and the drift capacity of the masonry infill walls strengthened with diagonally applied CFRP was recommended. It is concluded that the strength of the masonry infilled frames strengthened with diagonally applied CFRP can be satisfactorily predicted with the suggested procedure. The ultimate drift capacity of the masonry infill walls strengthened with diagonally applied CFRP strips was conservatively predicted to be 1.0%.