This study's objective was to look into the impact of lectin on the immune response to live and inactivated vaccines of Avian influenza, Newcastle disease virus, and Gumboro in broiler chicken. Moreover, a comparison between mushroom-extracted lectin and commercial lectin is investigated. Accordingly,100 broiler chicken were divided into 4 groups each one consisting of 25 chicken: the first group is -ve control, and the second one was treated with extracted lectin only. Followed by a third group, which is treated with commercial lectin only. Finally, the fourth group was treated with both extracted and commercial lectins. The vaccination program was VAXXITEK^® HVT+IBD in the hatchery, then ValleyVac® Penta-Pro injection on the sixth day, and Nobilis® Gumboro 228E on the 16^th day in drinking water. Lectin dose is 0.25 ml/L of drinking water for 2 days before live vaccines and 2 days after inactivated vaccines. After that, samples were collected before and after 48 hrs lectin administration in case of Infectious Bursal Disease (IBD). Otherwise, samples were taken 48 hrs before and 10 days after lectin administration in case of Highly Pathogenic Avian Influenza (H5N1) and Newcastle Disease Virus (NDV). Then, 3 samples from each group in each measurement are extracted for testing. The results obvious that there is no change in immune response in four groups to the Newcastle vaccine before and after lectin, indicating no effect of lectin on NDV immunity. Additionally, the titre of avian influenza after lectin administration is the same as before lectin, indicating no effect of lectin on H5N1. On the other hand, there is a superior impact of mushroom-extracted lectin on the immune response of IBD that the antibodies titre of the extracted lectin increased four times rather than the commercial lectin.