Two simple and selective methods for determination of stannous ion in radiopharmaceutical kits are proposed. One of this permits the estimation of stannic ion. The first method unsed is a potentiometric titration of Sn2+ in HCl medium, using KIO3 solution under nitrogen gas and a platinum redox electrode. The second method consists of a complexometric titration of tin (Sn2+ and Sn4+) using an EDTA standard solution at pH 5.5–5.6 without the use of nitrogen gas. The procedures employed indicate that both methods can be used for routine quantitative determination of tin in most labeled radiopharmaceuticals.