Sensitive and reproducible flow injection spectrophotometric method for determination of fluoxetine in pharmaceutical preparation has been developed. The method is based on base hydrolysis of the drug. The hydrolyzed product methylamine is reacted with sodium nitroprusside. The absorbance of the resulting colored product was measured spectrophtometrically at 510 nm using flow injection method. The method showed a linear range 0.5-25 mg/L with a molar absorptivity of 2.19 x 10(4). The % recovery for determination of flouxitine in formulations was found to be 99.7±0.18-99.4±0.22. The limit of detection and quantification was calculated and found 0.15±0.01 mg/L and 0.29±0.03 mg/L respectively. The proposed method was successfully applied to the pharmaceutical preparations-capsules and tablets