A rapid and feasible chromatographic method for determining atenolol, metoprolol, alprenolol, oxprenolol, acebutolol and propranolol by non-suppressed ion chromatography is proposed. The mobile phase consisted of 50 mM nitric acid in an aqueous solution of 4% (v/v) acetonitrile. Detection limits are in the range 0.1-2.7 mg l-1. The method was successfully applied to the determination of beta-blockers in several pharmaceutical formulations.