Disclosed are a common mode filter and a manufacturing method thereof. The common mode filter in accordance with an aspect of the present invention includes: a substrate; a filter layer including a coil and a dielectric layer and disposed on the substrate and configured to remove a signal noise; and a magnetic layer being laminated on the filter layer, and a surface of the filter layer being joined with the magnetic layer can be formed to be flat by having the coil embedded in a surface of the filter layer being joined with the magnetic layer in such a way that one surface of the coil is exposed.