The attempt to enhance sensitivity, resolution, and response time of vibration frequency sensing technology; this study investigates the effect of injecting olive oil into a solid core photonic crystal fiber (PCF) (i.e. large mode area, and endless single mode area) on the combined optical properties, and examine practically it's applicability in sensing technology of seismic waves based on the optical photonic crystal fiber injected with olive oil, raised from fluorescence spectrum of olive oil which shows high nonlinearities when irradiated with CW (532nm) laser diode radiation. Photonic crystal large mode area fiber was injected with olive oil using the capillary property. The sensor produced in this work was investigated to be worked on such structure. Three different types of vibration sources were subjected to the two-story simulated building structure and the Photonic crystal fiber proposed sensor setup was investigated on such structure. Many previous researches motivate this research, some of them had gone through the sensitivity of ordinary optical fibers to vibration and seismic wave, which is found to be highly sensitive, more accurate, provide good immune from around noises, and large dynamic range along with high resolutions. Other researches went through making a wireless sensing system in multi-story building to increase the buildings safety. The main conclusion of this thesis is that the Photonic crystal fibers can be used as vibration sensor and adding olive oil to PCF has the ability to enhance its sensing properties. The minimum detected vibration was 7Hz and the minimum step between any two detected frequencies was 1Hz.