Abstract: Phase testing technology can meet the online test demands of radomes in different shapes. Designing the optimal transformation curve to complete the fitting connection between the rectangular transmission waveguide and the circular radiation antenna via numerical simulation can effectively reduce the antenna voltage standing-wave ratio (VSWR), achieving the high-gain transceiver for the test probes, improving the test effectiveness. In the condition of maintaining the VSWR parameters, secondary curvature adjustment for the antenna aperture can accommodate the test stability requirements of radomes in different shapes. Low-VSWR reflection phase test in the molding of multiple radome models, which improves the effectiveness of monitoring and verifies the correctness of simulation results.