The invention discloses an immunization device for breeding in a large-scale pig farm. The device comprises a water supply mechanism, a vaccine supplying mechanism and a waterer device; the waterer device comprises a waterer and pig house water tanks; the water supplying mechanism comprises a shell, a permanent magnet, a water passing flux tube, a conductive magnet plate, an activation box and a water purification filter; the water passing flux tube is located in the shell, and water collection chambers are formed in the two ends; the two ends of the water passing flux tube extend out of the shells, and the water inlet end of the water passing flux tube is communicated with the water purification filter; the water outlet end of the water passing flux tube is separately communicated with water supplying mechanism one-way valves of the pig house water tanks in all breeding houses through water supplying and conveying pipes; a vaccine supplying mechanism comprises a vaccine preparation box and vaccine conveying pipes, the vaccine preparation box is separately communicated with vaccine supplying mechanism one-way valves of the pig house water tanks in all the breeding houses through the vaccine conveying pipes. The immunization device which is simple in structure, low in cost and capable of achieving a uniform immunization effect and is applied to the field of breeding in large-scale pig farms is provided.