The present invention relates to a thickness measurement method. The thickness measurement method comprises the following steps: a first measuring probe and a second measuring probe are configured to respectively measure a distance D1 between the first measuring probe and the surface, facing the first measuring probe, of a reference block and a distance D2 between the second measuring probe and the surface, facing the second measuring probe, of the reference block; the measurement thickness of the reference block is calculated: E=L-D1-D2, and the thickness compensation value is calculated: F=E-D, wherein L is the distance between the preset moving plane of the first measuring probe and the preset moving plane of the second measuring probe and D is the thickness true value of the reference block; the first measuring probe and the second measuring probe are also configured to respectively measure a distance d1 between the first measuring probe and the surface, facing the first measuring probe, of a workpriece to be measured and a distance d2 between the second measuring probe and the surface, facing the second measuring probe, of the workpriece to be measured; and the thickness value d of the workpriece to be measured is obtained according to the formula: d=L-d1-d2-F. According to the invention, the thickness measurement method has high measurement efficiency and high precision.