In order to meet the requirements of terahertz high-resolution detection and real-time processing, the photoconductive antenna is used to generate and detect terahertz time-domain spectral signals. Based on the field programmable gate array, the functions of terahertz time-domain spectrum acquisition, Wiener filtering deconvolution processing, transmission and host computer display are realized. The collected terahertz time-domain spectral data is subjected to Wiener filtering deconvolution processing to achieve the effect of restoring terahertz signals, improve time resolution and noise reduction. The data is transmitted to the host computer by Ethernet transmission for real-time display. In view of the wide pulse width after deconvolution of terahertz signals in actual detection, it is proposed to introduce a frequency-related function into the Wiener filtering deconvolution algorithm to optimize the algorithm, so that the pulse width of the signal becomes narrower and the detection accuracy is improved. Compared with the original algorithm, the signal-tonoise ratio of the optimized Wiener filter deconvolution algorithm is increased by 7 dB, the pulse width is reduced by 0. 2 ps, and the higher detection resolution is realized. The algorithm is implemented in FPGA, the accuracy error is less than 0. 7%, the processing efficiency is improved by 14. 29 times, and the post-processing time of the host computer is reduced.