Abstract: Disclosed is a method for preparing a strontium-82/rubidium-82 generator. The method includes: filling a column volume with a sorbent made of hydrated tin (IV) oxide; passing through the column an initial solution with strontium-82 radionuclide, which also contains ions of stable isotopes of calcium and strontium; and washing out rubidium-82 with a saline solution of 0.9% sodium chloride. In order to achieve a breakthrough of strontium-82 or strontium-85 below permissible levels, 0.01 and 0.1 kBq per 1 MBq 82Rb, respectively, when passing not less than 17 liters of saline solution through columns with a volume of not less than 1.6 cm3 and a dry sorbent weight of not less than 3.8 g, a specific activity of strontium-82 in the initial solution is not less than 90 GBq (2400 mCi) per mg of stable strontium cations for a generator with an activity of 3700 MBq (100 mCi).