This paper presents an experimental and numerical model of carbon fiber reinforced polymer (CFRP) retrofitted concrete beams with and without intermediate notches, developed to predict the impact load, energy response, cracking pattern and interfacial stress distribution under drop-weight impact. Considering a drop-weight falling from different heights, a CFRP sheet was bonded to the bottom surface of the beam. The specimen’s drop-weight impacts were established for retrofitted and un-retrofitted simply-supported notched concrete beams. A nonlinear finite element model was developed and calibrated to analyze the interfacial stress field, failure modes, cracking patterns and damage sequences. The results obtained numerically in terms of load–time, load–displacement and energy–time curves were compared to those given by the authors’ experimental tests and also to those given in the literature. For un-retrofitted beams, the impact time was very short, with failure at the center of the beam. For notched beams, the impact load decreased as notch depth increased, owing to the local loss of rigidity at the center of the concrete beam. For the retrofitted beam, however, the impact time was quite long, with a very high impact load, because the beam was more resistant, with rebound.