The utility model relates to a nerve root displacement length measuring tool for central paralysis side neck seven-displacement operation. The measuring ruler comprises a measuring ruler body and a nerve root straight guide groove, the front section of the measuring ruler body is long and narrow, the rear section of the measuring ruler body is wider than the front section, the nerve root straightguide groove and the measuring ruler body are arranged in parallel and connected, and the front end of the nerve root straight guide groove corresponds to the zero-scale position of the measuring ruler body. According to the utility model, accurate measurement of the displacement length of the central paralysis side neck seven nerves can be realized, the nerve root is prevented from being pulled in the measurement, and the measurement operation is simpler and more convenient.