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A dumbbell-shaped polystyrene (PS) sample, where rings are attached on both ends of a linear chain, was anionically synthesized by a coupling reaction between highly-purified ring PS (R-30; Mw = 33.7 kg/mol) with two diphenylethylene (DPE) type vinyl groups and bifunctional living linear PS (L-80; Mw = 84.0 kg/mol). The crude coupling product obtained was confirmed to include a targeted dumbbell polymer in addition to unreacted L-80 and R-30, and a single-tail tadpole polymer as byproducts. To isolate the dumbbell polymer, successive size-exclusion chromatography (SEC) and interaction chromatography (IC) fractionations were performed. It was found out that the dumbbell chain (D-30/80/30; Mw = 147 kg/mol) with sufficiently high purity (99.9%) was separated from the tadpole polymer with a single-tail in IC mode just due to a small difference in their chain architectures, i.e., the presence of the small rings on either one or both chain ends of a linear chain. This is the first report on successful preparation of a dumbbell-shaped polymer with high molecular weight and high purity, and the present product must be suitable for investigation of accurate physical properties.