Highly simple, sensitive and selective method is developed for the spectrophotometric determination of Metronidazole (MDZ) antibacterial drug either in pure form or in pharmaceutical formulations. This method is based on reduction of potassium permanganate by Metronidazole drug in sodium hydroxide solution to give green manganate ion which recorded at 610 nm. The method produced linear responses in the concentration range 4.28 – 59.91 µg mL⁻¹ with limit of detection (LOD) and limit of quantification (LOQ) 0.21 and 0.69 µg mL⁻¹ for Metronidazole drug respectively. The apparent molar absorptivity is 0.865 × 10⁴ L mol⁻¹ cm⁻¹, Sandell sensitivity is 0.019 µg cm⁻² and correlation coefficient is 0.951. The method is highly reproducible and has been applied to a wide variety of pharmaceutical formulations and the results compare favourably with those of official methods.