Abstract: This paper demonstrates the three-dimensional system in package (SiP) design for high-density multi-chip modules based on organic substrate stacking. TheSiPmodule is operating in Ka-band (transmit) and K-band (receive). The organic substrate is stacked with a ball grid array (BGA) to integrate the transceiver module with the two frequency band antennas. For the active-chip part, the bonding wire design, the electromagnetic radiation isolation and the heat treatment of the high-power chip are the focus of this paper. For the passive components, including microstrip bandpass filter, DC-AC isolation block and antenna design. The system has a multi-band, miniaturization, low profile, high gain advantage, in the future millimeter-wave wireless communication system has broad application prospects.