A high sensitive bending sensor based on eccentric core fiber (ECF) Mach–Zehnder modal interferometer (MZI) with direction recognition ability is proposed and demonstrated. The MZI-based bending sensor is fabricated by fusion splicing a piece of ECF in between two standard single mode fibers with a small lateral core-offset. Due to the eccentric location of the core of the ECF, a bend applied on the ECF-based MZI can cause an elongation or shortening of the eccentric core, which makes the ECF-based MZI suitable for directional bending measurement. The bending characteristics are investigated experimentally within the curvature range of 0–1.11 $\text{m}^{-1}$ . The bending sensitivities of the sensor are 13.49 nm/ $\text{m}^{-1}$ at the bending direction of 0° and −18.4 nm/ $\text{m}^{-1}$ at the direction of 180° corresponding to the interference dip at the wavelength of 1553.22 nm.