The structural behavior of perforated composite web plate girders under shear loading is studied. Five steel plate girders have been tested. Two of them are reference girders, not perforated and perforated. The perforated webs in the three other girders are strengthened with carbon fiber reinforced polymer (CFRP) laminates in different patterns. The diameter of the central circle opening is 300 mm, where is 60% of the web depth. It is found from the experimental work that the ultimate shear load for the perforated composite web plate girder is higher than the reference perforated girder in a range of 100% to 134% depending on the orientation of the fiber in CFRP laminates. Through the experimental results, new formulas are presented to predict the ultimate shear load of perforated strengthened steel girders by CFRP laminates. A nonlinear finite element analysis is carried out for the tested plate girders using the package software program (ANSYS V.14.5). The analytical results contain the distribution of VonMises stresses, which is useful to have a better understanding to the results obtained from the experimental tests.