The invention discloses a miniaturization dual-channel OFDM communication system which comprises an FPGA core chip, an FPGA core chip minimum system peripheral circuit, a DSP chip, a DSP chip minimum system peripheral circuit, an ADC sampling chip, a DAC converting chip, a kilomega network interface chip, a level conversion chip and a power chip. An intermediate frequency signal is converted by the ADC sampling chip to be in a digital mode to be sent into the FPGA core chip to be processed to form a baseband signal, the baseband signal is transmitted to the DSP chip for data processing through an EMIF interface, and the processing result is uploaded to an upper computer through the kilomega network interface chip; transmitted data are downloaded into the DSP chip for processing through the kilomega network interface chip to generate OFDM baseband signal data, the OFDM baseband signal data are transmitted to the FPGA core chip through the EMIF interface, digital up conversion is achieved in the FPGA core chip, and the DAC conversion chip is controlled to generate an intermediate frequency analog signal. An achieving method of the system includes seven steps.