To improve the uncertainties caused by the inappropriate diffusion model fitting in the IVIM-MRI, an optimal model mapping method has been proposed and demonstrated its usefulness. Here, we investigated the effect of the SNR in the method. Six different SNR data sets, derived by changing the numbers of average (NA) of six sets of DWI volumes, were analyzed. Then, the resultant maps reached a steady-state when the NA is four or higher. This study revealed that further investigations on b-value distribution optimization and denoising are necessary to obtain such high SNR data within practical scan time.