In the present work, we prepared copper nanoparticles suspend in aqueous environments by pulse laser ablation (PLA) of pure copper target in distilled water and then irradiated by (Nd+3:YAG) laser light (1064 nm). The peak position of Plasmon resonance absorbance of green colored nanoparticles was noticed at 630 nm . We have implemented the photodeposition technique to deposit Cu- nanoparticles on optical fiber end using laser light and a prepared Cu- nanoparticles suspend in aqueous environments. Using SHG:( Nd+3: YAG) (532 NM) pulse laser light and copper nanoparticles suspend in aqueous environments. Surface Plasmon resonance curves of an optical fiber-based sensor were investigated. Effect of laser pulse repetition rate, on structure, and nanoparticles size was studied by analysis of the ultraviolet-visible absorption spectra and AFM analysis of copper nanoparticles .The optical sensor was assembled using a LD light source, a spectrometer and an optical fiber immersed in copper nanoparticles colloidal as a sensor to measure the refractive index of aqueous media. The response and the sensitivity of the optical fiber sensor was investigated .Good agreement was obtained with respect to the resonance peak location and the shape of the curves. Consequently, these results enabled us to predict the ideal functioning conditions of the sensor.