The invention belongs to the technical field of flue gas treatment and environmental protection for cement kilns, and particularly relates to a dust SCR denitration device and technology for a cementkiln. The dust SCR denitration device comprises a rotary kiln, a kiln tail residual gas treatment system and a kiln head residual gas treatment system; the kiln tail residual gas treatment system comprises a five-stage cyclone preheater, an SP furnace, a dust remover, an SCR reactor, a high-temperature blower, a humidifying tower / waste heat boiler, a kiln tail bag dust removing unit, a kiln tail exhaust blower and a kiln tail chimney; the five-stage cyclone preheater is connected to the kiln tail of the rotary kiln; the cyclone dust remover is arranged in front of the SCR reactor for flue gasdust removal, the content of flue gas dust at the SCR reaction is lowered, the number of pores of a honeycomb catalyst can be increased, and the overall height of the catalyst and the reactor can be effectively lowered on the condition that the cubic number and the number of layers of the catalyst are not changed; the pressure loss of the whole reactor is lowered, power of the blower at the rear end can be reduced, and energy consumption is lowered.