Poultry industry is playing an important economic role in Pakistan. Newcastle disease is causing major economic loss to poultry industry. Propolis, a honey bee product, possessing many pharmacological properties and which is widely used in folk medicine. In current study, a total of 90 broiler chicks were purchased. These chicks were divided into six experimental groups: A, B, C, D, E and F (15 birds in every group). Chicks in group A were negative control (without infection and without supplementation). B group chicks were positive control for ND Infection (experimentally infected without any supplementation). The chicks in group C were positive control for propolis and were given 500mg propolis per kilo gram (kg) of diet and were not given ND infection. Group D, E and F were supplemented with propolis at rate of 250, 500 and 750 mg/kg in diet, respectively. Supplementation of propolis was provided from 1st. Infection was given on day 14. On day 1, 13 (pre-exposure), 17, 19 and 21 (post-exposure) blood was collected for Heamagglutination Inhibition (HI) test against ND. Group F shows protective antibody titer (GMT of Lag2 of HI = 3.25) as compared to positive control group B (GMT of Lag2 of HI = 0.00) antibody titre. The average weight gain was highest for group F. Mortality rate in positive control group was 100% while in group F, mortality rate was 26.67%. Gross pathological lesions were also significantly different with respect to proventricular haemorrhages, button ulcers in intestine, tracheal lesions and haemorrhages in the brain. Histopathology of bursa, spleen, thymus, cecal tonsils, trachea and lungs shown significant differences from group B to other groups. It was concluded that propolis have immuno modulatory effects. Propolis protects the bird from ND virus by interfering with its multiplication process. It also promotes growth performance of broiler birds and help the birds to survive against lethal ND infection. 1482424653.php