An error determination apparatus for determining a measurement error that occurs when a workpiece is measured by a coordinate measuring machine, the error determination apparatus includes an information acquisition part that acquires a) motion error information indicating a result of measuring a motion error of the coordinate measuring machine and b) design information of the workpiece, a measurement position specification part that specifies a measurement position on the workpiece on the basis of the design information, an error determination part that determines a measurement error occurring in the measurement at the measurement position due to the motion error on the basis of the motion error information, and an output part that outputs the measurement error determined by the error determination part.