In order to analyze low-coherent signal characteristics of turbid material, Monte Carlo(MC) numerical model is established. The Gaussian distribution of optical intensity and coherent gate of optical source are introduced into numerical simulation. An accelerated method is introduced into simulation of coherent intensity of turbid medium. Under condition of forword scattering, anisotropy factor g=0.9, the results of scaling method match with those of MC simulation with mean relative error of 2.37%. When g decreases to 0.5, and mean relative error increases to 4.69%. In calculation of coherent signals of different depths, similar data in surface layer are gotten by the two methods. In experiment, optical signals from 0 to 1 mm depth in the mixture liqid of IntralipidTM and India ink are measured by low-coherent system and fitted by accelerated Monte-Carlo method succesfully.