Abstract This paper presents a polymer optical fiber (POF) based temperature sensor. The operation principle of the sensor is the variation of the POF mechanical properties with the temperature variation. Such mechanical properties variation leads to a variation on the POF output power when a constant stress is applied on the fiber due to the stress-optical effect. The fiber mechanical properties are characterized through a dynamic mechanical analysis and the output power variation with different temperature is measured. The stress is applied on the fiber by means of a 180° curvature on it and supports are positioned on the fiber to inhibit the variation of its curvature with the temperature variation. Results show that the sensor proposed has a sensitivity of 1.04×10-3 °C-1, linearity of 0.994 and root mean squared error of 1.48°C, which means a relative error of below 2% that is lower than the ones obtained for intensity-variation based temperature sensors. Furthermore, the sensor is able to operate on temperatures up to 110°C, which is higher than the ones obtained for similar POF sensors in literature.