Simple fiber-optic sensors are used to measure the refractive index of cholesterol solution. The purpose of this study was to measure the refractive index of cholesterol solution with the principle of laser propagation of He-Ne wavelength 632.5 nm through optical fiber bundle and absorption of laser beam in cholesterol solution and reflected back by flat mirror then ray reflected through fiber optic bundle so detected By the SL-818 silicon detector in the form of output voltage. Laser propagation of laser-guided optical fiber bundles as an intensity-based profile through a medium of cholesterol solution with varying refractive index values. The variation of refractive index of cholesterol solution is 1.325 - 1.331. The measurement  results showed that the maximum output voltage showed a linear decrease to the increase of refractive index of cholesterol solution with sensitivity of 3,871 V and linearity of 97,34%.