The utility model relates to coke oven accessory equipment in coal coking industry, in particular to a mortar spray machine for a coke oven. The mortar spray machine is provided with an air inlet, an air outlet and a mortar outlet pipe, pipelines are connected with the inside of the mortar spray machine, the mortar spray machine is externally connected with a spray gun mortar inlet and a spray gun air inlet, the spray gun mortar inlet and the spray gun air inlet are led into the mortar spray machine, the air inlet of the mortar spray machine is positioned on the upper surface of the mortar spray machine, and an air inlet pipe is arranged at an extending position of the air inlet inside the mortar spray machine. The mortar spray machine for the coke oven has the advantages that 1 raw materials entering the mortar spray machine are automatically stirred, so that labor intensity is reduced, 2 only one person is needed for operation, so that complicated coordination work is eliminated, and operation is easy and in control, 3 spray repair sensitivity, spray repair accuracy and spray repair efficiency are greatly improved, and 4 by means of improvement, raw material sedimentation at the bottom of a tank is completely eliminated, labor efficiency is improved, labor and labor intensity are reduced, and cost is greatly reduced.