Crushing device for building materials

The utility model discloses a building material smashing device which comprises a smashing device body and a briquetting device, the smashing device body is arranged on one side of the briquetting device, supporting legs are fixedly connected to the four corners of the bottom end of the smashing device body, and a material inlet is formed in the top end of the smashing device body; a first motor is arranged in a second motor shell, the first motor drives a driving shaft and a driven shaft to rotate through a driving gear and a driven gear correspondingly, first smashing blades are arranged on the outer sides of the driving shaft and the driven shaft correspondingly, second smashing blades are arranged below the driven shaft, and building materials enter the smashing device from a material inlet; and building materials can be fully crushed through the first crushing blades and the second crushing blades, the phenomenon that subsequent briquetting work is affected due to the fact that one-time crushing is not t