In this study, a fiber curvature sensor was proposed based on a rough side-polished single-mode fiber with a sensitizing technology. In addition, the transmittance of sensitive area in case of the fiber curvature sensor was accurately measured using the pulse self-reference demodulation technique. The experimental results obtained based on the cantilever beam denote the linear response coefficient of the sensor sensitive area is 0.593 and that the noise amplitude in the measurement system is 5.9×10 ^-5. The curvature resolution of the system can become 9.95×10 ^-5 m ^-1 when the cantilever beam displacement is converted to curvature. Furthermore, the curvature sensor has a simple structure and a wide response bandwidth and can be used in a time-division multiplexing system.