A multi-channel sharing apparatus and a multi-channel sharing method are disclosed. The multi-channel sharing apparatus comprises a companion chip and an application processor. The companion chip comprises a first compression circuit, a second compression circuit and a transmission circuit. The application processor comprises a receiving circuit and a network module. The first compression circuit generates a first bit stream and a second bit stream according to the first channel data. The second compression circuit generates a third bit stream and a fourth bit stream according to the second channel data. The transmission circuit transmits the first, second, third and fourth bit streams. The receiving circuit receives the first, second, third and fourth bit streams. The network module outputs the first network package according to the second bit stream, and outputs the second network package according to the fourth bit stream.