Refractive index profile is required to calculate waveguide properties. This profile can be reconstructed by analyzing its near field image. The measured near field image, which is obtained by using inverse propagation mode near field method, is processed by a computer image processing programme. The image processing procedures adopted in this work include background noise substraction, gamma correction, smoothing and filtering with neighborhood averaging filter. These procedures produced a parabolic refractive index profile. By fitting half of refractive index profile in x and y direction from fiber center using non linear least square regression technique, it is known that the index profile had a power factor, alpha equals 2.218958 in y direction and (alpha) equals 2.626216 in x direction. Fitting process is also derived for variety refractive index profile according to power-law profiles ((alpha) -profiles), with power factor, (alpha) equals 1,2,4, and 10 to the measured refractive index profile. The best fitted curve is determined by its minimum deviation.