PURPOSE: To attempt improvement of quality of a tire and early detection of a defective tire by easily performing the judgement of the raw tire shape.

CONSTITUTION: A virtual raw tire N is found by laminating the specific tire constituent members Q, R, T, S, F on a carcass line having a natural balance shape H by using a manufacturing data, and the shape judgement of the outer surface of the actual rear tire is performed on the basis of the outer surface coordinate of the virtual raw tire N, thereby manufacture of the criterion can be eased, and the defective tire can be eliminated in the step of the raw tire.