The invention discloses an air purification and sterilization device for a farm, and relates to the technical field of environmental protection equipment. The air purification and sterilization devicecomprises an air inlet pipe 1, a cylinder body 11 and support feet 3, wherein the air inlet pipe 1 is mounted at the lower portion of the cylinder body 11 and is communicated with an inner cavity ofthe cylinder body 11, and the support feet 3 are mounted at the lower end portion of the cylinder body 11; a water washing assembly, a drying assembly, a sterilization assembly and a peculiar smell absorbing assembly are arranged in the inner cavity of the cylinder body 11; an access cover 15 is arranged on the outer cylindrical surface of the cylinder body 11; and an exhaust assembly and a wastewater drainage port 4 are correspondingly formed in the upper and lower ends of the cylinder body 11. The device has the beneficial effects of simple structure, good treatment effect and the like, andis suitable for being used in various scales of pig farms, chicken farms, duck farms and the like.