In the present study, a series of pyrazoline derivatives were synthesized. The chemical structures of the compounds were elucidated by IR, H-1-NMR, C-13-NMR and FAB+-MS spectral data and elemental analyses. The synthesized compounds were screened for their antimicrobial activities. All compounds exhibited the highest antibacterial activity against P. aeruginosa. All compounds except compounds 1-(chloroacetyl)-3-(2-furanyl)-5-(4chlorophenyl)-2-pyrazoline and 1-(chloroacetyl)-3-(2-thienyl)-5-(3,4-methylenedioxyphenyl)2-pyrazoline are more effective than ketoconazole against C. albicans, whereas compounds 1-(chloroacetyl)-3-(2-furanyl)-5-(4-chlorophenyl)-2-pyrazoline, 1-(chloroacetyl)-3-(2-thienyl)-5-( 3,4-methylenedioxyphenyl)-2-pyrazoline and ketoconazole showed the same level of antifungal activity against C. albicans.