Load Flow Analysis in Power System is used to determine the system's parameters itself. The computation process closely related with system's optimization problem. Newton-Raphson method for load flow iteration has been used for long time. Genetic Algorithms method's application as one of optimization methods worked in giving solution for the system, through application procedure on genetic operators in process. Both methods apply in simulation to compute simplified 12 Bus East Java 150 KV. From the comparison of the two methods above we have thatr Jacobian matrix is needed to apply in Newton-Raphson method meanwhile it is not needed in Genetic Algorithms method. The computation time for Newton-Raphson method is quite fast comparing with Genetic Algorithms'.