A reliable method was established for the determination of tin in pure copper by flow-injection hydride generation atomic absorption spectrometry. The determination of tin in pure copper often suffers from interference from the copper matrix. In this work, cupferron was used as a chelating reagent to separate the copper from the tin. At pH 3.0, copper ion could form stable cupferron complex and could be removed from sample solution by chloroform extraction without loss of tin. After most of the chloroform dissolved in the aqueous solution had been removed, tin could be determined at 224.6 nm with the optimized conditions of 1.0% HCl as carrier solution and 0.8% m/v NaBH 4 as reductant. A pure copper standard reference material, SRM 396 unalloyed copper, was analyzed with the proposed method. A calibration curve was obtained with a linear range of 113 mg L 21 and a detection limit of 0.25 mg L 21 . The experimental results obtained for certified values were 0.76 + 0.3 and 0.8 + 0.03 mg g 21 , respectively. A recovery of 93.7 + 2.6% (n ¼ 5) was obtained. This established that the method was applicable to the determination of tin in pure copper with good accuracy and precision.