The present disclosure relates to an interposer structure and a manufacturing method thereof. The interposer structure includes a first dielectric layer, a conductive pad, and a bump. The conductive pad is disposed in the first dielectric layer, wherein a top surface of the conductive pad is exposed from a first surface of the first dielectric layer, the conductive pad further includes a plurality of connection feet, and the connection feet protrude from a bottom surface of the conductive pad to a second surface of the first dielectric layer. The bump is disposed on the second surface of the first dielectric layer, and the bump directly contacts to the connection feet. Through the aforementioned interposer structure, it is sufficient to achieve the purpose of improving the electrical performance of the semiconductor device and avoiding the signal being loss through the TSV.