In order to explore the influence of length and width of CFRP as well as anchor spacing on the reinforcement effectiveness of CFRP plates on reinforcement concrete beams (RC beams) under secondary load, 7 anchored damaged FRP reinforced concrete beams are used as test beams, 1 unanchored beam is used as a control beam, and structural indicators such as ultimate load and bending strength are analyzed in the result. The conclusion is that composite CFRP plate can effectively prevent the early peeling and failure of carbon plates and improve the ultimate bearing capacity of the beam. When the width of the CFRP plate decreases, the thickness increases and the steel plate anchor spacing increases appropriately, the ultimate bearing capacity and ductility of the beam are significantly improved.