The invention provides a method for roasting a cement clinker through sulphur coal by a dry-process rotary kiln. The method comprises the following steps of: (1) preparation of raw materials: the material preparation scheme of intermediate saturation ratio, intermediate-low silica modulus and high aluminum-oxygen modulus is adopted, and the materials are that 0.90+/-0.02 of KH, 2.5+/-0.1 of N, and 2.0+/-0.1 of P; and the raw materials comprise 84% of limestone, 4% of high siliceous shale, and 12% of siliceous shale; and (2) roasting of clinker: the sulphur coal is adopted and used as the fire coal and contains 7.0 to 8.0% of sulphur content and 12 to 15% of volatile matter; the air inlet angle of a coal-injection duct of the rotary kiln is set to 34 degrees, the inner air opening is in a full opening state, the outer air opening degree is set to reach 50 to 70%, the throat of a smoke chamber is set to reach 1100mm; when in roasting, the temperature of an outlet of a decomposing furnace is controlled to 860 to 880 DEG C, the temperature of the smoke chamber is controlled to reach 950 to 1050 DEG C, and the rotation speed of the rotary kiln is controlled to more than 3.8 revolutions per minute at the same time; the crust on the smoke chamber is removed twice every eight hours in each shift during roasting, as well as removing the crust on a gooseneck of the decomposing machine every 12 hours. According to the method, the total sulfur in the fire coal for the dry-process rotary kiln is expanded to reach 7.0 to 8.0%, the qualified clinker can be normally roosted, and no influence is brought to the output and the quality.