Disclosed is a power package for an electrical device of an Electronic Control Unit (ECU) in an Electric Power Steering (EPS) system, the power package including: a housing which is formed with an upper part and a lower part and is formed to be in a two-step structure where substrate layers are provided on each of the upper and lower parts; a Printed Circuit Board (PCB) layer which is provided on the lower part of the housing and has a path line formed thereon to flow a current; and an LTCC layer which is provided on the upper part of the housing, is connected to the PCB layer through wire-bonding, and is formed of a Low Temperature Co-fired Ceramics. The power package for an electrical device can expand areas of the PCB and LTCC layers, thereby enhancing freedom degree of design of the PCB and LTCC layers and reducing a size of the entire case.