A new and highly sensitive spectrophotometric based flow injection analysis method has been developed for the determination of copper (II). N, N'-o-phenylene-bis (3-methoxysalicylideneimine) (H2IF) was used as a new chromogenic reagent. The absorbance was measured at λ max = 420 nm. Various factors affecting complex formation have been investigated. For example, the pH effect, reagent concentration was studied. Under optimum conditions, Beer's law was met in the range of 3.18-318 μg L−1 copper (II) concentration. The system required no mixing chamber and allowed a sample throughput > 60 sample per hour for 20 μL injection volume. The interaction of the various ions was investigated and the experimental results were reported. The proposed method has been successfully applied to the determination of the amount of copper (II) found in pharmaceutical samples and water samples. The validity and applicability of the method was confirmed by AAS and standard reference material SPS-WW2 (Wastewater) analysis. ARTICLE HISTORY