The invention belongs to the technical field of fertilizer processing, and discloses a smashing device for fertilizer processing. The smashing device comprises a machine frame, a smashing barrel and two sets of smashing rollers. Rotating shafts are arranged in the middle parts of the smashing rollers. A screening box is arranged below the smashing barrel and is further provided with a sliding block. The smashing device further comprises a moving part. The moving part comprises a rotary table, a first support rod, a second support rod and a third support rod, wherein the first support rod, thesecond support rod and the third support rod are sequentially hinged. The machine frame is further provided with an air blowing mechanism. The air blowing mechanism comprises a piston barrel, a disk and a piston. The smashing device further comprises a first connecting rod, a second connecting rod and a third connecting rod which are sequentially hinged. The end, far away from the second connecting rod, of the first connecting rod is fixed to the disk. The end, far away from the second connecting rod, of the third connecting rod is connected to the piston. An air inlet and an air outlet are formed in the piston barrel. By means of the smashing device for fertilizer processing, the problem that two sets of devices need to be used for smashing and screening materials in the prior art and thus smashing cost is high is solved.