Two series of substituted thiadiazolyl and oxadiazolylquinolines (3a-h, 4a-h, 7a-f, 8a-f and 9) were synthesized and screened for their antimicrobial activity. Some of the tested compounds showed promising activity. Compound 4b exhibited bactericidal activity against S. aureus at 31.25 μg/ml. While compound 8a showed distinct antifungal activity against C. albicans (MIC at 31.25 μg/ml). The detailed synthesis, spectroscopic and biological data are reported.