The traditional temperature sensor has some shortcomings in measuring the temperature of underground soil,such as poor corrosion resistance,vulnerable to electromagnetic interference and easy to be damaged. It is difficult to accurately and comprehensively obtain the long-term variation of soil temperature. In this paper,several distributed optical fiber temperature measurement techniques are compared and analyzed. It is proposed to use optical frequency domain reflection technology to monitor the temperature of underground soil. According to the characteristics of high precision and high spatial resolution of optical frequency domain reflection technology,the detailed monitoring scheme of optic fiber and the analysis of monitoring data are presented. In order to verify the advantages and feasibility of optical frequency domain reflectance technology in soil temperature monitoring,an indoor simulation monitoring test of soil temperature is carried out,and a set of fine temperature measurement device of soil temperature using optic fiber is designed. The optical frequency domain reflectance technology is used to monitor the temperature of soil and water in different containers. It shows that the result of optic fiber is basically consistent with the result obtained from the traditional method,but the distributed measurement can be realized by the optical fiber temperature measurement. It is remarkable compared with the traditional method. The good result of the soil temperature measurement is achieved.