A system controller of an optical disk recording and reproducing device writes test data in a test writable area of a loaded optical disk if it is an unused disk and calculates a maximum amplitude value of an RF signal at an inner radius. Then, it calculates the maximum amplitude value of a tracking error signal at the inner radius and further calculates the maximum amplitude value of the tracking error signal at the outer radius. After that, it calculates a primary approximate expression about a tilt from the maximum amplitude value of the tracking error signal at the inner radius and the maximum amplitude value of the tracking error signal at the outer radius. It further offsets the primary approximate expression by a difference between the tilt values that is obtained by subtracting the maximum amplitude value of the tracking error signal at the inner radius from the maximum amplitude value of the RF signal at the inner radius. As a result, a tilt control is performed in accordance with the RF signal of the virtual maximum amplitude value that is obtained by adding the difference between the tilt values to the primary approximate expression.