Disclosed is a device for separating radioisotope thallium-201. The device includes an evaporation unit for a solution vial, a first glass vial connected to a first valve and a second valve, an ion exchange column connected to a third valve, a second glass vial connected to a fourth valve and a fifth valve, a collection vial for receiving solution from the fifth valve, a product vial with a membrane filter and a vacuum unit connected to the first valve, the fourth valve and a sixth valve. This device can separate out high-concentration thallium-201 solution from which radioisotope thallium-201 can be obtained.