The fundamental function of wearable robots, muscular strength support, is typically evaluated using biological signals from the user. Although this approach is intuitive and user-friendly, it falls short of repeatability and objectivity. To address these issues, we introduce a method for performance evaluation that utilizes an anthropomorphic dummy robot(ADR). The ADR is capable of executing test movements while wearing a wearable robot, substituting a human operator. The consistent test motions by the ADR ensures both repeatability and objectivity. The effectiveness of the wearable robot in supporting muscular strength is assessed by measuring the energy expenditure of the ADR. An 11-DOF ADR was engineered to replicate standard test movements. We conducted experiments to evaluate the performance of a commercial passive wearable robot product using the ADR and our proposed methodology. Analysis of these test outcomes not only affirmed the reliability of the ADR-based testing approach but also yielded insights for optimizing wearable robot design.