There is provided a printed circuit board having a differential signal transmission line composed of non-skew-adjusting portions and skew-adjusting portions. The non-skew-adjusting portion consists of parallel conductive traces spaced apart by a spacing. The skew-adjusting portion consists of a pair of meander traces for the skew adjustment. The skew-adjusting portion include convex transmission line segments and concave transmission line segments. The convex transmission line segment has parallel traces having a differential trace pair spacing greater than the differential trace pair spacing in the non-skew-adjusting portion. The concave transmission line segment has parallel traces having a differential trace pair spacing smaller than the differential trace pair spacing in the non-skew-adjusting portion.