Optical sensors have attracted considerable attention in recent decades. Springs are used for a large variety of functions in industry including in sensor applications such as the measurement of force, acceleration, vibration, and pressure. In this study, a compression coiled spring and an optical fiber cable were combined to form a new optical fiber spring. The measurement part of the fiber optic spring was constructed by using a 3 dB fiber coupler and a fiber polarization beam splitter/combiner. During the study, a diode laser was used and silicon detectors measured the variations of the polarization state intensity. The spring constant of the optical fiber spring was obtained from decay of the free vibrations and Hooke's law. In conclusion, the new constructed fiber optic spring can be used in some industrial sensor applications.