The invention provides a desulfurization and denitration device and technology used for purifying coke oven smoke. The device comprises a smoke waste heat recovery device, a desulfurization reactor and an SCR denitration reactor in a sequential connection mode. The desulfurization reactor is provided with a first smoke inlet, a first smoke outlet and a bearing device, the SCR denitration reactor is provided with a second smoke inlet, a second smoke outlet and a bearing device, the bearing devices can move downwards, the first smoke inlet and the first smoke outlet enable the coke oven smoke to make countercurrent contact with active coke and/active carbon in the desulfurization reactor, and the second smoke inlet and the second smoke outlet enable the smoke which is subjected to desulfurization treatment to make cross-current contact with active coke and/or active carbon in the SCR denitration reactor. By the utilization of the device, the denitration efficiency reaches 80% or more, the desulfurization efficiency reaches 96% or more, the temperature in the regeneration reaction of active coke can be obviously decreased to 50 DEG C-75 DEG C, and therefore energy consumption is lowered.