A printed circuit board and a manufacturing method thereof. According to one embodiment, a printed circuit board may include a core part; and a conductor pattern disposed on at least one surface of the core part, the core part includes a glass core having a side portion that is polished or thinner than a central portion of the core. According to another embodiment, a method of manufacturing the printed circuit board may include cutting a glass plate to form a glass core; and removing cracks from at least one side surface of the cut glass core.