The invention provides a cooling barrel for production of compound fertilizer. The cooling barrel comprises a base, a support, a barrel body, a fixing ring, a cooling sleeve, a screening mesh, a fine material cavity, stirring blades, a rotary shaft, a motor, an air blower pipe, an air inlet, a coarse material opening, a fine material opening, a feed inlet, a feed pipe, an air blower site and an air blower opening, wherein the support is arranged on the base; the barrel body is fixed to the support through the fixing ring on the outer side of the barrel body; the left end of the barrel body is higher than the right end of the barrel body; the barrel body is sequentially provided with the cooling sleeve, the fine material cavity and the screening mesh from outside to inside; the rotary shaft coaxial with the barrel body is arranged in the middle of the barrel body, and the rotary shaft is provided with the four oblique stirring blades; the left side of the rotary shaft is electrically connected with the motor on the left side of the barrel body; the right side of the barrel body is provided with the air inlet and the coarse material opening; the fine material opening is formed in the lower right portion of the barrel body; the feed inlet is connected to the upper left portion of the barrel body through the feed pipe; the air blower pipe is connected to the left end of the air inlet; and the air blower pipe is wound in a gap between the screening mesh and the stirring blades. The cooling barrel has the beneficial effects that the cooling efficiency is high, the grain distribution of products is uniform, and the equipment cost is low.