The invention relates to a dustproof high and low voltage switching cabinet and a dust preventing and removing method thereof. The switching cabinet comprises a cabinet body, wherein an air inlet, a cabinet door and an air outlet are formed in the cabinet body; the air inlet is provided with a dust removing device; the dust removing device comprises a dust removing chamber, a dust collecting chamber and a dust removing assembly; the dust removing assembly comprises a protecting net, a first filtering group, an adsorption group, a second filtering group, a fan mechanism and a dust cleaning assembly; the dust removing assembly is used for removing dust entering air in the cabinet body and cleaning the dust into the dust collecting chamber; the protecting net, the first filtering group, the adsorption group, the second filtering group and the fan mechanism are sequentially arranged in the dust removing chamber from outside to inside. The dustproof high and low voltage switching cabinet and the dust preventing and removing method thereof have the advantages that dust with different particle sizes is filtered out and is prevented from entering the cabinet body, so that a dustproof spacein the cabinet body is ensured, the safety problem caused by the dust is reduced and dust removing and cleaning procedures can be automatically finished.