We develop a new noise suppression technique to perform distributed strain and temperature sensing based on a higher-speed configuration of Brillouin optical correlation-domain reflectometry even when a polymer optical fiber (POF) is used as a sensing fiber. We acquire the spectral difference between with and without reference light, leading to selective observation of the beat signal of Brillouin-scattered light and reference light, which is effective for distributed sensing. After experimentally showing the usefulness of this technique, we demonstrate POF-based distributed temperature sensing and dynamic strain sensing.