In order to make the fog cannon machine swing at a large angle in the pitch direction, the hydraulic fog cannon adopts a hydraulic pitch device, which is installed under the fog cannon blower and is connected to the diagonal rotating bracket and the underside of the blower respectively. The pitch device uses hydraulic drive to drive the push rod, thereby pushing the wind tube to swing up and down at a large pitch, so as to realize the precise dust removal of the fog gun machine and achieve a larger spray zero dust removal area. On the base of the zero gun machine, next to the pitch hydraulic device, a special device is designed to place the hydraulic motor, and a shell protection device is added to the motor to prevent the motor from being damaged due to long-term adverse weather conditions and improve the performance of the pitch hydraulic system. The service life is equivalent to increasing the service life of the fog cannon.