Bromazepam (7-bromo-1, 3-dihydro-5-(2-pyridyl)-2H-1, 4-benzodiazepin-2-one) was determined by formation the chelate compound with iron (II) followed by extraction from the organic phase into an aqueous solution. The absorption spectrum of the chelate compound in aqueous solution showed maximum absorbance at 580 nm and the absorbance was stable for about 5 hr at room temperature. The calibration curve was linear from 0.2 to 50 μg/ml of bromazepam and the sensitivity of the procedure was 0.2 μg/ml of bromazepam. This procedure was applied to the determination of bromazepam in rat blood. The recovery of added bromazepam from rat blood ranged from 96 to 100.5%, with a mean recovery of 99.1%.