Grinding method

A grinding method comprising:

• (a) a step of grinding a work surface by relatively moving a grinding wheel, on an outer peripheral surface of which a helical dressed groove having no intersection is formed, with respect to a workpiece in a first grinding direction which is tilted with respect to a forward reference direction perpendicular to an axis of the grinding wheel, while rotating the grinding wheel around the axis of the grinding wheel as a rotation center, in a state where the outer peripheral surface is brought into contact with the work surface of the workpiece;
• and
• (b) a step of grinding the work surface by relatively moving the grinding wheel with respect to the workpiece in a second grinding direction which is tilted with respect to a backward reference direction opposite to the forward reference direction, after the step (a),
• wherein when the grinding wheel is virtually moved for grinding in the forward reference direction, an extending direction of a virtual grinding trace formed by the dressed groove transcribed on the workpiece and the first grinding direction are tilted in mutually opposite directions with respect to the forward reference direction, and thus an absolute value of a tilt angle of the first grinding direction is smaller than an absolute value of a tilt angle of the extending direction of the virtual grinding trace, and
• wherein a rotation direction of a tilt from the forward reference direction to the first grinding direction and a rotation direction of the tilt from the backward reference direction to the second grinding direction are opposite to each other.