In allusion to the principle of Surface Plasmon Resonance (SPR) and the advantage of fiber sensor, fiber SPR sensor system was designed and realized based on the surface plasmon resonance effect, and data processing model was given. Data around the resonance area was processed by averaging method, in which the noise was proved as Gaussian distribution by skewness-peak method. Moreover, mean estimate and linear estimate models were used to estimate the resonant wave length through theoretical analysis. At the same time, the least sampling number was given to denoise on the condition that the precision was ensured. Result indicates that the whole processing workload is decreased by 2%, and the processing efficiency is improved.