A simple, rapid and efficient method of separation of strontion from calcium can be perfomed by using a solution of 2.5% NH4- EDTA, with pH adjusted to 4.80 to dissolve those cations. After, the solution is passed through a 25-28 ml column of the Amberlite 1R-120 (4+) cation exchange resin. Strontinum is quantitatively retained on the resin, while calcium passes through. After removal of ammonium ions with 0.25 to 0.75 normal solution of HC1, the strontium is eluted with 3 normal solution of HCl. The method was used to separate strontium and calcium from prepared strontinum-calcium mixture containing 0.36 mg of Sr with radioactive strontinum Sr-89 and 199.2 mg of Ca. The recovery of strontinum was 97.7, 97.0, and 98.6% in three replications and the recovery of calcium was 100.0, 99.9 and 99.7%. The strontinum was determined radiometrically with the "1000" Scaler, model SC-33, Tracerlab, Inc.