Department of Chemistry, Saurashtra University, Rajkot-860 005 Manuscript received 13 June 1988, revised 2 January 1989, accepted 2 February 1989 Some new 2,5-disubstituted-1,3,4-oxadiazoles have been prepared having 2-aryl-5- (4'-benzenesulphonamidophenyl)/(4'pyridyl) moiety. Benzene sulphonamidobenzoyl hydrazide/isoniazide was condensed with different aromatic acids in presence or phosphorous oxychloride. The structures or the compounds were supported by ir spectra. The products were screened for their antimicrobial activity.