This paper presents a hardware encryption system based on FPGA (Field-Programmable Gate Array) implementing the elliptic curve cryptography algorithm. Using FPGA as the core control unit, IoT (Internet of Things) data transmission terminals are connected to FPGA-specific external interfaces via USB/SPI interfaces. Data collected into the FPGA undergoes encryption and decryption using the FPGA’s internal hardware resources. The encrypted data is then converted into TCP/IP protocol packets and transmitted to a cloud server through the FPGA’s internal Ethernet interface circuit module. A detailed analysis and design of the hardware implementation of the elliptic curve encryption algorithm are provided. Simulation validation of the point multiplication algorithm was conducted on a computer platform with a quad-core 3.2GHz processor and 8GB of memory, using the Xilinx 5vlx20tff323 chip. The simulation results indicate that the maximum execution frequency reached 372.686 MHz, with a single point multiplication operation completed in 3328 . This significantly enhances the processing speed of the algorithm, bearing significant theoretical value and practical implications for advancing the security of the IoT ecosystem.