Prediction of total hull resistance has been investigated for many decades and it is still a challenging problem for naval architect. In this paper, the total resistance of round bilge monohull Model 100A is predicted by potential flow solver, Shipflow by Flowtech International AB, the commercial Reynold Average Navier Stroke (RANS) solver Fluent by Fluent, Inc., and analytical prediction by Slender Body Method (SBM). The total resistance was predicted by each code for the different model speeds (0.6m/s to 4.5m/s) and compared with experimental test data. The Fluent predictions were found to be in agreement with the experimental data in lower speed (0.6m/s to 2.5m/s). Shipflow results were more closed to experimental results than Fluent. Comparisons between the different solution methods were also discussed with the particular grid generation methods and numerical solution techniques. It is found that Slender Body Method can solve as easy and simple and it is effective to predict total resistance of thin ship monohull.