An optical fiber curvature sensor is fabricated by using a short section of polarization maintaining fiber (PMF) as the sensing component spliced in an optical fiber Sagnac loop. The length of the sensing element for the curvature sensing is about 142 mm. The sensitivity of the curvature measurement of 0.0344 m-1/pm is achieved experimentally. The propose sensor is more convenient and simply than that of photonic crystal fiber (PCF).© (2010) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.