Chloride penetration is the main reason for corrosion of steel bars in reinforced concrete in marine environment, salt lake area and saline soil area. Therefore, measurement of chloride distribution in reinforced concrete structures timely and accurately is of great significance for durability assessment, maintenance and repair of reinforced concrete structures under severe environment. In this paper, a solid-state Mn/MnO2 reference electrode with dense structure and stable performance, which can be embedded in concrete, was prepared by pressed powder method. Results showed that loading pressure is an important parameter that affects the strength and density of Mn/MnO2 electrode prepared. During preparation of Mn/MnO2 electrode, it is necessary to control the loading pressure. The suggested pressure loading pressure is 96 MPa. And the Mn/MnO2 electrode must be activated before use. After activated, the response time of the Mn/MnO2 electrode is less than 60 second.Also the Mn/MnO2 electrode has stable performance, good reproducibility and good resistance of polarization. The potential value of the Mn/MnO2 electrode increases linearly with the increase of temperature between 5℃ and 65℃. Besides, the pH value between 8 and 13 has almost no effect on the potential value of the Mn/MnO2 electrode. So, if the Mn/MnO2 electrode prepared in the way mentioned in this paper is used as reference electrode of chloride sensor, temperature of concrete at the location of chloride sensor is also needed to record simultaneously. And the potential value of the Mn/MnO2 electrode must be corrected by temperature.