Circuit board assembly and spaceborne computer

The invention provides a circuit board assembly and a spaceborne computer. The circuit board assembly comprises a shell, a PCB and heat conduction insulating oil; the shell defines a closed accommodating cavity, the PCB is arranged in the closed accommodating cavity, and an electronic device is arranged on the PCB. And a gap between the shell and the PCB is filled with heat-conducting insulating oil, so that heat generated by the electronic device is conducted to the shell through the heat-conducting insulating oil. According to the circuit board assembly, the PCB is arranged in the containing cavity defined by the shell, the heat-conducting insulating oil is adopted as a heat-conducting medium, after the containing cavity is filled with the heat-conducting insulating oil, the insulating oil can completely wrap the surfaces of the components, the heat dissipation area is increased to the maximum degree, and the effect that all parts on the PCB are uniform in temperature is facilitated; meanwhile, higher heat