The invention relates to a network video monitoring system based on FPGA chaotic encryption, comprising a server terminal, a client terminal and a system configuration terminal. The server terminal comprises a plurality of cameras, a video server, an encryption module and a signal sending module; the client terminal comprises a signal receiving module, a decryption module and a client terminal player; video frequency collected by the plurality of cameras is coded by the server, then input into the encryption module via the Ethernet and sent to the client terminal via the signal sending moduleafter encrypted; the signal receiving module of the client terminal receives the encrypted video data and then sends the data to the decryption module for processing and finally the client terminal player plays the video data; the encryption module and the decryption module are respectively an FPGA encryption board and a decryption board; the encryption process and the decryption process of the encryption module to video flow are as follows: the encryption module adopts a CPRS array which is cut and operates with a plain text data module 2, and then sent; and the receiving terminal of the decryption module obtains the same CPRS array, and then operates with a cryptograph module to realize decryption.