Uranium (VI) forms a yellow coloured water soluble complex with diacetyl monoxime isonicotinoyl hydrazone (DMIH) reagent in acidic buffer of pH 3.25 with ?max at 364 nm. The molar absorptivity and sandell’s sensitivity are 1.63 X 10 4 L.mol -1.cm-1 and 0.00307692 µg/cm 2, respectively. The Beer’s law validity range is 1.19–14.28 µg/mL. Uranium (VI) forms (M:L) 1:1 complex with DMIH and stability constant of the complex is 4.928 X 106 .The derivative spectrophotometric determination of U (VI) was carried out by measuring peak height method. The developed derivative spectrophotometric method was employed for the determination of uranium (VI) in rock and synthetic samples. The effect of various diverse ions was also studied.