In order to develop a low cost temperature measurement system based on FPGA, through analyzing the 1wire bus communication protocol of digital temperature sensor DS18B20 in this paper, strictly according with the communication timing requirements of sensors, the 1wire bus communication controller (IP core) had been designed with finite state machine (FSM). Moreover, the 1wire bus controller core and other modules form a complete temperature measurement and display system on EP2C8Q208C8 FPGA development board, the final test results show that the 1wire bus controller not only can drive the DS18B20 stably to measure the temperature, and the temperature measurement system based on FPGA in the hardware implementation cost low to 410 Logic Elements (LEs), a temperature measurement time only 754.7ms.