The purpose of this research is to study the simulation model for the overhand card shuffling. We assume that the distribution of cut-position is beta, and the distribution of thickness of the shuffling is discrete uniform. Researchers have studied nine models of card shuffling under the simulation with simulation size of 10,000. We define the randomness level [Due to the limit of system, equation can't display correctly. Please see the equation in hardcopy or full text file] for all nine model comparisons. From the study the top–card–high–thickness model is the best with minimum number of shuffling of 7 to achieve the acceptable randomness level. The top–card–moderate–thickness model is moderately good with minimum number of shuffling of 17. And, the under–card–high–thickness is the worst model because the acceptable randomness level cannot be achieved with number of shuffling of 50 times.
