During one year period 432 chicken flocks with variable disease condit ions were surveyed for the prevalence of various respiratory problems. Among 432 flock surveyed 18(4.16%) were positive for 18. Regarding agewise incidence maximum (35.71%) infection was recorded in 1-5 week age group. Seasonwise maximum (66.66%) incidence was recorded in winter season. Maximum IBV was isolated from lungs, trachea and kidneys. IBV affected embryoes showed curling and dwarfing alongwith severe haemorrhages on the egg shell membrane. Different physico chemical parameters of eggs from hens infected with IB were signific antly different from normal eggs. Studies of gross and histopathological alterations in different visceral organs of chickens affected with infect ious bronchitis were studied. In IB trachea, larynx, lungs, oviduct and kidneys were the target organs.