A waste gas purification device for pharmacy and chemical industries comprises a bottom plate, pushing devices, a purification device, a gas inlet device, a concentration device, first gas outlet devices, water inlet devices, a second gas outlet device and a recovery device, wherein first supporting blocks and first rollers are arranged on the bottom plate; each pushing device comprises a first air cylinder, a first support, a first pushing rod and a first pushing plate; the purification device comprises a purification tank, a first transverse plate, a first retaining frame, a first concentration plate, first cross rods, a first pipeline and first fixing frames; the gas inlet device comprises a gas inlet pipe, a first supporting rod, a first oblique rod, a second support, a gas inlet hopper, a first partition board, a first fan, a third support and fourth supports; the concentration device comprises a concentration frame, a second transverse plate, second oblique rods, a first filtering frame, a first concentration hopper and a first sealing ring; each first gas outlet device comprises a second partition board and a first connection rod. The waste gas purification device can completely purify waste gas in workshops of the pharmacy and chemical industries and clear dust and other impurities in the workshops.