An experiment was conducted to examine the efficacy of spray vaccination against Newcastle disease (ND). Four different coarse sprayers and four different diluents were compared in particle size, immune response and respiratory reaction. The smaller particle size of sprayer was, the better efficacy was and the more respiratory reactions were appeared. Of four diluents, antibody responses and resistance to challenge were higher with skim milk and gelatin, respectively .When day-old broiler chicks with maternal antibodies were vaccinated by coarse. sprayer B with B$_1$strain diluted in 1% skim milk, they showed 100% protection at two weeks of age and 50% from 4 to 8 weeks of age. Another group which boostered at 2 weeks of age by drinking water vaccination showed 100%, 70%, 50%, 40% protection at 2, 4, 6, 8 weeks of age, respectively. Although spray vaccination against ND in this experiments showed similar efficacy, compared to conventional methods, this method may not be appropriate in our field condition because of respiratory vaccinal reaction.