A high-accuracy load measuring apparatus capable of enlarging a measurement range includes a loading section provided at one end of a long and narrow beam. A support supports the beam at a side closer to the other end of the beam than the loading section. A displacement sensor includes a capacitive sensor and is provided to measure a displacement of the loading section. The beam includes a pair of long and narrow plate-like legs arranged in parallel while being spaced apart in a thickness direction and a connecting portion connecting ends of the plate-like legs at a side of the loading section. The beam is supported on the support to have a changeable length between a supported position by the support and the loading section. Each plate-like leg includes a slot, which is a long and narrow hole formed along a length direction in a widthwise central part.