Computer mainframe dust removal device

A computer mainframe dust removal device comprises a machine body. A working cavity with an upward opening is formed in the machine body, a rotatable motor main shaft is arranged in the working cavity, and threads are fixedly formed in the motor main shaft. A first threaded sleeve is fixedly arranged on the threads in a threaded mode, a first transition bevel gear is fixedly arranged at the lowerend of the first threaded sleeve, an outer fixing frame is arranged on the first transition bevel gear in a left-and-right symmetry mode, and a dust discharging pipe is fixedly arranged in the outer fixing frame. According to the computer mainframe dust removal device, the dust can be separated from the inner wall of a mainframe through dust removal brushes, then the dust is collected by a dust absorption pump, the phenomenon that after the dust drops down, the secondary pollution is caused is avoided, dust clusters which are originally fluffy are wetted and contracted through water addition,and therefore the effect of saving the space is achieved; and then the contracted dust is collected, and the unnecessary water which exists after the dust clusters are wetted is filtered by a filtering screen and then is subjected to secondary utilization through a water suction pump.