A semiconductor device package includes a dielectric layer, a first conductive pattern and a first semiconductor device. The dielectric layer has a first surface, wherein a surface uniformity of the first surface is substantially equal to or less than 5%. The first conductive pattern is disposed on the first surface of the dielectric layer, wherein the first conductive pattern includes a first conductive trace, and a line width of the first conductive trace substantially ranges from about 0.5 μm and about 2 μm. The first semiconductor device is disposed on the first surface of the dielectric layer and electrically connected to the first conductive pattern.