The invention discloses a method for producing cement clinkers from dried carbide slag completely instead of natural limy materials, which relates to the field of building materials. Firstly, three auxiliary materials (including sand rock, coal ash and sulfur acid residue) are compounded, pulverized and sieved, and the fine powder is fed into a dryer. Then, the carbide slag with a water content less than or equal to 12% is fed into the dryer, and undergoes intensive heat exchange with the hot flue gas at the charge side, realizing complete drying and mixture. The crude material powder is fed into first-stage, second-stage and third-stage cyclone cylinders to undergo multiple suspension heat exchange with the hot flue gas, and then enter a rotary kiln for calcination. The hot flue gas inside the klin undergoes the heat exchange in a pipeline calciner and a wind pipe and then reversely flows into the third-stage, second-stage and first-stage third-stage cyclone cylinders, the dryer, a cyclone dust collector, a system fan and an airbox pulse bag-shaped dust collector sequentially, and the purified gas is discharged into the external atmosphere. The coal powder jets into the calciner at the charge side for further combustion, and the crude material powder undergoes decomposition reactions: Ca(OH)2-H2O+CaO. The clinker burned in the rotary kiln is cooled by a grate cooler and then delivered to a clinker storage room. In the invention, the waste carbide slag is completely dried by using the exhaust gas at the discharge side, and the heat consumption for clinker combustion is reduced by about 25%, thereby realizing energy conservation and exhaust reduction.