The invention discloses a cadmium reference electrode and a manufacturing method thereof. According to the invention, in the prior art, a cadmium reference electrode is easily corroded during the usage process and the test on the cadmium voltages of the positive and negative electrodes of a battery can be carried out only when the corroded cadmium reference electrode is replaced by a new one. Thecost is greatly increased due to the above facts in the prior art. The cadmium reference electrode and the manufacturing method thereof are provided to solve the above problems in the prior art. The cadmium reference electrode comprises a cadmium rod and an installation sleeve, wherein the cadmium rod is inserted into the installation sleeve. The lower end of the cadmium rod extends out of the installation sleeve. A sealing anti-corrosion sleeve is arranged on the outer wall of the cadmium rod. An anti-corrosion sealant is filled between the inner wall of the installation sleeve and the outerwall of the sealing anti-corrosion sleeve. A plurality of annular easy-to-break grooves are formed in the outer wall of the cadmium rod in the axial direction at equal intervals. A plurality of annular grooves are formed in the outer wall of the installation sleeve and are in one-to-one correspondence with the plurality of annular easy-to-break grooves. A vertically-arranged cutting-off groove isformed in the outer wall of the installation sleeve. The outer wall of the installation sleeve is movably sleeved with a cutting knife mechanism used for cutting off the installation sleeve. The upperend of the cadmium rod is connected with a lead-out wire.