An ultraviolet sterilization and disinfection device for air purification, comprising: an ultraviolet sterilization and disinfection chamber with an air inlet and an air outlet, a blower configured to adjust the wind speed of the air stream within the ultraviolet sterilization and disinfection chamber to 1-5 m/s and to adjust the flow rate of air, and one or more low pressure ultraviolet lamps arranged within the ultraviolet sterilization and disinfection chamber; wherein, in order that the ultraviolet dosage of the ultraviolet sterilization and disinfection device reaches a reference dosage of 5 mJ/cm 2, the ratio of the volume of the ultraviolet sterilization and disinfection chamber to the flow rate is less than 0.8 s; at a reference flow rate of 10 m 3 /h, the output power of the lamps required to reach the reference dosage of 5 mJ/cm 2 is less than 22 W; characterized in that for the ultraviolet lamps, the inner diameter being between 30 mm and 36 mm and the tube current density being 0.250-0.800 A/cm 2; the inner diameter being between 26 mm and 30 mm and the tube current density being 0.280-0.850 A/cm 2; the inner diameter being between 12 mm and 15 mm and the tube current density being 0.335-1.000 A/cm 2; the inner diameter being between 10 mm and 12 mm and the tube current density being 0.300-1.000 A/cm 2; the inner diameter being between 8 mm and 10 mm and the tube current density being 0.300-0.900 A/cm 2; the inner diameter being between 5 mm and 8 mm and the tube current density being 0.250-0.800 A/cm 2; or the inner diameter being between 3 mm and 5 mm and the tube current density being 0.280-0.900 A/cm 2; wherein the material in the low pressure ultraviolet lamps used for mercury vapor pressure control is liquid mercury; or the material in the low pressure ultraviolet lamps used for mercury vapor pressure control is an alloy containing bismuth, indium, tin and mercury or an alloy containing bismuth, plumbum, tin and mercury. an ultraviolet sterilization and disinfection chamber with an air inlet and an air outlet, a blower configured to adjust the wind speed of the air stream within the ultraviolet sterilization and disinfection chamber to 1-5 m/s and to adjust the flow rate of air, and one or more low pressure ultraviolet lamps arranged within the ultraviolet sterilization and disinfection chamber; wherein, in order that the ultraviolet dosage of the ultraviolet sterilization and disinfection device reaches a reference dosage of 5 mJ/cm 2, the ratio of the volume of the ultraviolet sterilization and disinfection chamber to the flow rate is less than 0.8 s; at a reference flow rate of 10 m 3 /h, the output power of the lamps required to reach the reference dosage of 5 mJ/cm 2 is less than 22 W; characterized in that for the ultraviolet lamps, the inner diameter being between 30 mm and 36 mm and the tube current density being 0.250-0.800 A/cm 2; the inner diameter being between 26 mm and 30 mm and the tube current density being 0.280-0.850 A/cm 2; the inner diameter being between 12 mm and 15 mm and the tube current density being 0.335-1.000 A/cm 2; the inner diameter being between 10 mm and 12 mm and the tube current density being 0.300-1.000 A/cm 2; the inner diameter being between 8 mm and 10 mm and the tube current density being 0.300-0.900 A/cm 2; the inner diameter being between 5 mm and 8 mm and the tube current density being 0.250-0.800 A/cm 2; or the inner diameter being between 3 mm and 5 mm and the tube current density being 0.280-0.900 A/cm 2; wherein the material in the low pressure ultraviolet lamps used for mercury vapor pressure control is liquid mercury; or the material in the low pressure ultraviolet lamps used for mercury vapor pressure control is an alloy containing bismuth, indium, tin and mercury or an alloy containing bismuth, plumbum, tin and mercury.