A rotary measuring device includes a measuring unit, a centrifugal force error calculation block, and a weight value calculation block. The measuring unit includes a measuring plate and a load cell. The load cell has a fixed end and a free end on which the measuring plate is disposed. The centrifugal force error calculation block calculates, on the basis of a first measured value outputted from the load cell in a state where the measuring unit is rotating, an angular displacement θ with respect to a horizontal plane of the load cell in the vicinity of the free end. The weight value calculation block calculates a weight value of the object on the basis of the angular displacement value and a second measured value outputted from the load cell in a state where the measuring plate is receiving the load resulting from the object.