The measurement results of cylindrical worms vary greatly under different probe tip diameters on the Gear Measurement Center (GMC). Considering toroidal enveloping cylindrical worm (ZC1 worm) as an instance, after analysing the worm grinding coordinate system, the probe correction method based on normal vector centering (NVC) is established. The theoretical coordinate values of the points on the normal equidistant line which is rotated into the axial section are used as the probe tip center trajectory. Experiments were carried out with probe tip diameters of 1.0mm, 1.5mm and 2.0mm for the worm tooth profile measurement on a GMC. Compared with the traditional method, the variation between the profile deviations results using the proposed method become smaller and the variation of “profile deviation, total” is reduced from 8.3μm to 0.5μm, the profile slope deviation variation is reduced from 8.6μm to 0.5μm. The proposed method in ZC1 worm tooth profile measurement can effectively reduce the variation between the measurement results under different probe tip diameters on GMC, and also the methodology can be applied on other kinds of cylindrical worms. The method has significance for other curved profiles measurement on coordinate measurements.