The present invention is intended to provide a body motion grading system that allows the grading less likely to be affected by the difference among the builds of target persons subjected to grading. The present invention provides body motion grading system (1) including body position information acquisition unit (11) configured to acquire body position information of a target person subjected to grading in time series, body part recognition unit (12) configured to recognize a position of each part in the acquired body position information in time series and relatively recognize positions of body parts with reference to a certain body part, body motion grading unit (13) configured to conduct grading by comparing a position of a body part recognized by the body part recognition unit with a preliminarily prepared comparison condition in time series, and grading result display unit (14) configured to display a grading result.