Abstract: The tensile behavior of composite laminate containing penetrated damage and the optimization of repair designing parameters were studied after being flush repaired on double-sides. The results demonstrate that the recovery of failure strength of repairing specimens could reach 80% after double-sided flush repaired. The strength of repair specimens can be recovered to the maximum, when scarf ratio is 1∶40, and covering layers number is three with the layer's orientation is the same as the mother plate's layer which is close to covering layers. Double-sides flush repairing is familiar to any thicknesses and any lay-up ways of the mother laminates. A 3D finite element analysis was studied to verify the test result using ABAQUS software. In the model, every layer was set as a section, then give it the orientation of each layer. The analysis data are agree with the test results.