External bonding of fiber reinforced polymer (FRP) plates to reinforced concrete (RC) beams has been found to be an effective technique for flexural strengthening. This paper presents an analytical parametric study on the behavior of RC continuous beams flexurally strengthened with externally bonded FRP plates on the upper and lower fibers, conducted using simple uniaxial nonlinear finite element model (UNFEM). The study investigated the effect of three key parameters on the behavior and moment redistribution of FRP-strengthened continuous beams. The investigated parameters were the length of the FRP plate, the width and the thickness of the FRP plate, and the ratio between the area of the FRP plate to the concrete area. The investigation resulted in a number of important conclusions reflecting the effects of the studied parameters on the behavior of the strengthened beams.