A bumper reinforcement structure capable of achieving a weight reduction while still securing required bending strength in a bumper reinforcement structure with closed cross-section structure configured by joining together an inside member and an outside member. A bumper reinforcement is formed with two closed cross-sections configured by joining together three top-to-bottom flanges of an inner panel to three top-to-bottom flanges of an outer panel. The flanges of the inner panel are disposed in the same front-rear direction position as that of the wall portions that configure the closed cross-sections.